Transaction Handling

The Firebird architecture allows high transaction concurrency.Transaction save points (nested transactions) are also supported.All Firebird transactions are ACID compliant.ACID is explained below:

Atomicity: ensures that transactions either complete in their entirety or not at all, even if the system fails halfway through the process.
Consistency: ensures that only valid data will be written to the database.If a transaction is executed that violates the database’s consistency rules, the entire transaction will be rolled back and the database will be restored to a state consistent with those rules.If a transaction successfully executes, it will take the database from one state that is consistent with the rules to another state that is also consistent with the rules, without necessarily preserving consistency at all intermediate levels.
Isolation: ensures that transactions are isolated from one another, even if several transactions are running concurrently.Concurrency refers to a state within the database where two or more tasks are running simultaneously.This way, a transaction’s updates are concealed from the rest until that transaction commits.Transactions in Firebird are isolated within separate contexts defined by client applications passing transaction parameters.
Durability: ensures that once a transaction commits, its changes survive within the database, even if there is a subsequent system crash.

There are several parameters available to configure transactions to ensure consistency within the database.These parameters invoke the concept of concurrency.To ensure data integrity, there are four configurable parameters affecting concurrency: isolation level, lock resolution mode, access mode, and table reservation.

Isolation Level: A transaction isolation level defines the interaction and visibility of work performed by simultaneously running transactions.There are four transaction isolation levels according to the SQL standard:

READ UNCOMMITTED

A transaction sees changes done by uncommitted transactions.

READ COMMITTED

A transaction sees only data committed before the statement has been executed.

REPEATABLE READ

A transaction sees during its lifetime only data committed before the transaction has been started.

SERIALIZABLE

This is the strictest isolation level, which enforces transaction serialization.Data accessed in the context of a serializable transaction cannot be accessed by any other transaction.

In isql, a transaction is begun as soon as the utility is started.The transaction is begun in SNAPSHOT isolation, with a lock resolution set to WAIT.Since the Firebird isql utility accepts DDL, DML and other commands, transactions are handled accordingly, in the following ways:

DDL statements are committed when issued at the SQL prompt in two ways:
- Automatically, if SET AUTODDL is on, which is the default, and if the statement completed successfully.To turn it off, issue a SET AUTODDL OFF statement at the isql prompt, or on the commandline with -⁠n(oautocommit).
- When COMMIT statements are included in the script.
DML statements are never committed automatically.You must issue a COMMIT statement to commit any DML changes to the database.
You can use various SHOW commands in isql to query database metadata.Metadata is stored in system tables.When a SHOW command is issued, it operates in a separate transaction from user statements.They run as READ COMMITTED background statements and show all committed metadata changes immediately.

Users can specify the access mode and level of isolation for the next transaction, and explicitly commit the current transaction by using the SET TRANSACTION statement.Executing SET TRANSACTION starts a new transaction.

Here is an example:

-- Use Firebird defaults
SQL> SET TRANSACTION;
-- Use read committed
SQL> SET TRANSACTION READ COMMITTED;

If a transaction is already active when you run SET TRANSACTION, isql will prompt if you want to commit the current transaction.Choosing ‘y’ will commit the current transaction, while ‘n’ will roll back the current transaction.

If the [isql-set-keep-tran-params] option is on isql will remember the last SET TRANSACTION statement executed explicitly, and use it when it needs to implicitly start a transaction.

Note	The `set transaction` statement is not shown in `isql`'s `SET HELP` because it is a Firebird statement, and not an `isql` command, consult the Language Reference for your version for the syntax and further details.

Script Handling

A batch of DDL and/or DML statements in a text file is known as a script.Scripts can be used to create and alter database objects.These are referred to as Data Definition Language (DDL) scripts.Scripts that manipulate data by selecting, inserting, updating, deleting or performing data conversions, are called Data Manipulation Language (DML) scripts.

One of the most important tasks handled by isql is to process scripts.It can handle both DDL and DML Scripts, but they should be included in separate scripts to avoid data integrity problems.This script processing feature of isql allows the linking of one script to another using the isql command INPUT <filespec>.Scripts statements are executed in order that they appear in the script file.The default setting in isql for AUTODDL is set to ON.You may use the [isql-set-autoddl] command to control where or when DDL statements will be committed.

Note

The AUTODDL setting only affects DDL statements.It doesn’t commit DML statements.If you mix DDL and DML statements within the same interactive session, then the AUTODDL commits do not commit your DML changes.For example:

SQL> set autoddl on;

SQL> insert into test(a) values (666);
SQL> commit;

SQL> select * from test;

           A
============
         666

SQL> insert into test(a) values (999);
SQL> select * from test;

           A
============
         666
         999

SQL> create table another_test(b integer);
SQL> rollback;

SQL> select * from test;

           A
============
         666

Scripts can redirect their output to a log file using the OUTPUT file_name command.This can be entered directly at the isql prompt, or as part of a script file itself.

docnext count = 84

`Isql` Commands

Isql commands affect the running of isql itself and do not affect the database or data in any way.These commands are used to display help, run scripts, create listings and so on.You can easily see a list of the available commands by typing the help command which will produce the following output:

SQL> help;
Frontend commands:
BLOBDUMP <blobid> <file>   -- dump BLOB to a file
BLOBVIEW <blobid>          -- view BLOB in text editor
EDIT     [<filename>]      -- edit SQL script file and execute
EDIT                       -- edit current command buffer and execute
HELP                       -- display this menu
INput    <filename>        -- take input from the named SQL file
OUTput   [<filename>]      -- write output to named file
OUTput                     -- return output to stdout
SET      <option>          -- (Use HELP SET for complete list)
SHELL    <command>         -- execute Operating System command in sub-shell
SHOW     <object> [<name>] -- display system information
    <object> = CHECK, COLLATION, DATABASE, DOMAIN, EXCEPTION, FILTER, FUNCTION,
               GENERATOR, GRANT, INDEX, PACKAGE, PROCEDURE, ROLE, SQL DIALECT,
               SYSTEM, TABLE, TRIGGER, VERSION, USERS, VIEW
EXIT                       -- exit and commit changes
QUIT                       -- exit and roll back changes

All commands may be abbreviated to letters in CAPitals

Each of these commands will be discussed in the following sections.Note the last line of output from the help command.It explains that each of the commands may be abbreviated to just those letters displayed in capital letters.In the following discussion, the optional characters will be displays, as above, in lower case letters.For example, the input command will be shown as INput to indicate that the characters 'put' are optional.

`BLOBDUMP`

BLOBDUMP blob_id filename

This command allows you to copy a BLOB from the database into an external file.It is the responsibility of the user to ensure that the correct file type is used — don’t call an image file something.txt when it should be a jpeg for example.

Blobdump requires two parameters, a blob id and a filename.The latter is simple, but the former is more convoluted.You pass the blob id as a pair of hexadecimal numbers, separated by a colon.The first number is the relation id number for the table in question, and the second is a sequential number within the database.You will see this pair of numbers when you select any BLOB column’s data from a table — it is displayed above the BLOB contents, assuming that the display of BLOBs is turned on.See the [isql-set-blobdisplay] command below for details.

SQL> set blobdisplay off;

SQL> select proj_id, proj_desc
CON> from project
CON> where proj_id = 'MKTPR';

PROJ_ID         PROJ_DESC
======= =================
MKTPR               85:10

SQL> blobdump 85:10 project.jpg;

SQL> blobdump 85:10 project.txt;

The blob id required in the above example is the '85:10' value.You will notice that I have dumped this BLOB to both a jpeg and a text file.Isql gave no errors for the fact that I attempted to dump the BLOB to a jpeg file when the BLOB in question is text.Attempting to open the jpeg file with any image viewers will, however, result in an error.The text file opens happily in any of the assorted text viewers or editors installed on the system.

`SHELL`

SHELL

This command allows you to temporarily exit from isql and use a shell session to carry out some further processing.On exiting from the shell, you will return to isql.You cannot use the isql session that activated the shell while the shell session remains open.

SQL> shell;

$ cat test.log

       COUNTRY                                CUSTOMER
       DEPARTMENT                             EMPLOYEE
       EMPLOYEE_PROJECT                       FRED
       JOB                                    PROJECT
       PROJ_DEPT_BUDGET                       SALARY_HISTORY
       SALES

$ exit

SQL>

`SHOW`

There are a number of settings and options that can be changed to suit how you wish isql to operate.The show command allows you to view the way that these have been set up by the set commands, or by other options.These are discussed below.

`EXIT`

EXIT

The exit command will commit any uncommitted work and exit from isql.

`QUIT`

QUIT

The quit command will roll back any uncommitted work and exit from isql.

`BLOBVIEW`

BLOBVIEW blob_id

This command is similar to [isql-command-blobdump] above, but only requires the blob id parameter as the BLOB data will be displayed in an editor.

SQL> blobview 85:10;

The contents of the selected BLOB are displayed in an external editor.When the editor is closed, control returns to isql.You cannot use isql while the editor is open.

Note	`BLOBVIEW` may return an “Invalid transaction handle” error after you close the editor.This is a known bug.To correct the situation, start a transaction manually, with `SET TRANSACTION;`

`EDIT`

EDIT [filename]

This command allows you to edit an existing file.This may be a file of SQL commands to be used by the isql input command (see below) or any other text file.The file must, however, already exist.

If no filename is supplied, a history of all your previous commands will be displayed for editing.Please note that when you exit from the editor in this case, the commands left in the buffer at the end of the edit will be executed as a script file.

`HELP`

The help command has been discussed above.

`ADD`

ADD table_name

This command, when passed a table name, prompts you for each column’s data and adds a row to the table.You may add as many rows as you wish, as the command continues until either an error occurs, or the kbd:[Enter] key is pressed without data.If you wish to set a column to NULL, type it in exactly as shown.

SQL> add country;

Enter data or NULL for each column.  RETURN to end.
Enter COUNTRY>Scotland
Enter CURRENCY>GBP

Enter COUNTRY>


SQL> commit;

`COPY`

COPY from_table_name to_table_name [other_database]

The copy command allows you to copy most of the structure of a table to a new table, in the current database or to a different one.Unfortunately it has a couple of problems:

It shells out to the commandline to do the work, and connects to the receiving database using an application named isql.If, like me, your system has renamed isql to isql-fb, you will actually end up running the wrong isql application and confusing error messages will be the only result.
When using an embedded connection, and the ServerMode is set to Super/ThreadedDedicated (the default), a copy within the same database will fail because the database file is opened with exclusive access by the first isql session.
It assumes that isql will be on the $PATH or %PATH%.
You need to define ISC_USER and ISC_PASSWORD for the child isql process to log in to the receiving database to create the table.This is very insecure.
Because of the need for ISC_USER and ISC_PASSWORD, the receiving database must be running on the same server as the source database.
The data in the table is not copied to the receiving database.Only the following parts of the table’s structure is copied.
- Domains required to recreate the table.This only applies if the copy is to another database.
- The table itself will be created.
- Primary key constraint, if there is one.
- The index used to support the primary key constraint, if there is one.
Not all structure of the table is actually copied.Missing are:
- Foreign Key constraints.
- Check constraints.
- Indices other than the primary key index.
- Triggers.
- All table data.

If you wish to copy to a different database, then the other database must be on the same server as the current one.You cannot, for example, connect to a database on a server named tux, and copy a table to a database running on the server tuxrep.The copy command has no way to allow you to pass a username and/or password and, equally, setting ISC_USER and ISC_PASSWORD only affects databases on the current server.

tux> $ export ISC_USER=SYSDBA
tux> $ export ISC_PASSWORD=secret
tux> isql employee
Database:  employee, User: sysdba

SQL> -- MAke a copy of the employee table into this database.
SQL> copy employee employee_2;

SQL> -- Compare table structures...
SQL> show table employee;
EMP_NO                          (EMPNO) SMALLINT Not Null
FIRST_NAME                      (FIRSTNAME) VARCHAR(15) Not Null
LAST_NAME                       (LASTNAME) VARCHAR(20) Not Null
PHONE_EXT                       VARCHAR(4) Nullable
HIRE_DATE                       TIMESTAMP Not Null DEFAULT 'NOW'
DEPT_NO                         (DEPTNO) CHAR(3) Not Null
                                CHECK (VALUE = '000' OR
                                (VALUE > '0' AND VALUE <= '999') OR VALUE IS NULL)
JOB_CODE                        (JOBCODE) VARCHAR(5) Not Null
                                CHECK (VALUE > '99999')
JOB_GRADE                       (JOBGRADE) SMALLINT Not Null
                                CHECK (VALUE BETWEEN 0 AND 6)
JOB_COUNTRY                     (COUNTRYNAME) VARCHAR(15) Not Null
SALARY                          (SALARY) NUMERIC(10, 2) Not Null DEFAULT 0
                                CHECK (VALUE > 0)
FULL_NAME                       Computed by: (last_name || ', ' || first_name)

CONSTRAINT INTEG_28:
  Foreign key (DEPT_NO)    References DEPARTMENT (DEPT_NO)
CONSTRAINT INTEG_29:
  Foreign key (JOB_CODE, JOB_GRADE, JOB_COUNTRY)
  References JOB (JOB_CODE, JOB_GRADE, JOB_COUNTRY)
CONSTRAINT INTEG_27:
  Primary key (EMP_NO)
CONSTRAINT INTEG_30:
  CHECK ( salary >= (SELECT min_salary FROM job WHERE
                        job.job_code = employee.job_code AND
                        job.job_grade = employee.job_grade AND
                        job.job_country = employee.job_country) AND
            salary <= (SELECT max_salary FROM job WHERE
                        job.job_code = employee.job_code AND
                        job.job_grade = employee.job_grade AND
                        job.job_country = employee.job_country))

Triggers on Table EMPLOYEE:
SET_EMP_NO, Sequence: 0, Type: BEFORE INSERT, Active
SAVE_SALARY_CHANGE, Sequence: 0, Type: AFTER UPDATE, Active

SQL> show table employee_2;
EMP_NO                          (EMPNO) SMALLINT Not Null
FIRST_NAME                      (FIRSTNAME) VARCHAR(15) Not Null
LAST_NAME                       (LASTNAME) VARCHAR(20) Not Null
PHONE_EXT                       VARCHAR(4) Nullable
HIRE_DATE                       TIMESTAMP Not Null DEFAULT 'NOW'
DEPT_NO                         (DEPTNO) CHAR(3) Not Null
                                CHECK (VALUE = '000' OR
                                (VALUE > '0' AND VALUE <= '999') OR VALUE IS NULL)
JOB_CODE                        (JOBCODE) VARCHAR(5) Not Null
                                CHECK (VALUE > '99999')
JOB_GRADE                       (JOBGRADE) SMALLINT Not Null
                                CHECK (VALUE BETWEEN 0 AND 6)
JOB_COUNTRY                     (COUNTRYNAME) VARCHAR(15) Not Null
SALARY                          (SALARY) NUMERIC(10, 2) Not Null DEFAULT 0
                                CHECK (VALUE > 0)
FULL_NAME                       Computed by: (last_name || ', ' || first_name)

CONSTRAINT INTEG_93:
  Primary key (EMP_NO)

SQL> -- Check indices on both tables...
SQL> show indices employee;
NAMEX INDEX ON EMPLOYEE(LAST_NAME, FIRST_NAME)
RDB$FOREIGN8 INDEX ON EMPLOYEE(DEPT_NO)
RDB$FOREIGN9 INDEX ON EMPLOYEE(JOB_CODE, JOB_GRADE, JOB_COUNTRY)
RDB$PRIMARY7 UNIQUE INDEX ON EMPLOYEE(EMP_NO)

SQL> show indices employee_2;
RDB$PRIMARY27 UNIQUE INDEX ON EMPLOYEE_2(EMP_NO)

SQL> -- Check data counts on both tables...
SQL> select count(*) from employee;

       COUNT
============
          42

SQL> select count(*) from employee_2;

       COUNT
============
           0

The copy command only works provided your isql application is really named isql.In addition, if you have lots of data in the table, you still have to copy it manually as the copy command will only copy the table structure.Remember that the new table will have no triggers, no foreign keys, no indices — other than the primary key one — and no data.

Note	It is possible that the `copy` command will be removed from `isql` at some future release.

`INput`

INput filename

This command enables the user to execute a number of commands from a script file rather than manually typing them all into isql at the prompt.The script may contain any mix of DDL and/or DDL commands, along with isql commands to redirect output, change options, etc.

SQL> shell;

$ cat test.sql
drop table fred;
commit;

$ exit;

SQL> show table fred;
A                               INTEGER Nullable
B                               INTEGER Not Null

SQL> input test.sql;

SQL> show table fred;
There is no table FRED in this database

`OUTput`

OUTput [filename]

This command redirects all output that normally is displayed on the screen, to a specific file.If a filename is supplied, all subsequent output goes to that file and is not displayed on screen.If no filename is supplied, output is once more redirected to the screen.

SQL> output test.log;

SQL> show tables;

SQL> output;

SQL> shell;

$ cat test.log

       COUNTRY                                CUSTOMER
       DEPARTMENT                             EMPLOYEE
       EMPLOYEE_PROJECT                       FRED
       JOB                                    PROJECT
       PROJ_DEPT_BUDGET                       SALARY_HISTORY
       SALES

`SET`

There are a number of settings and options that can be changed to suit how you wish isql to operate.These settings are changed by the set command which is discussed below.

`Isql` Set Commands

As explained in [isql-commands], you may enter the help set command to drill down into the various options available for the set command.These are all discussed below.Note that the output from the help set command only lists isql-specific commands;it does not list the set transaction statement and other Firebird statements that start with set.The help set command produces the following output (from Firebird 5.0):

SQL> help set;
Set commands:
    SET                    -- display current SET options
    SET AUTOddl            -- toggle autocommit of DDL statements
    SET BAIL               -- toggle bailing out on errors in non-interactive mode
    SET BLOB [ALL|<n>]     -- display BLOBS of subtype <n> or ALL
    SET BLOB               -- turn off BLOB display
    SET COUNT              -- toggle count of selected rows on/off
    SET MAXROWS [<n>]      -- limit select stmt to <n> rows, zero is no limit
    SET ECHO               -- toggle command echo on/off
    SET EXPLAIN            -- toggle display of query access plan in the explained form
    SET HEADING            -- toggle display of query column titles
    SET KEEP_TRAN_params   -- toggle to keep or not to keep text of following successful SET TRANSACTION statement
    SET LIST               -- toggle column or table display format
    SET NAMES <csname>     -- set name of runtime character set
    SET PER_TABle_stats    -- toggle display of detailed per-table statistics
    SET PLAN               -- toggle display of query access plan
    SET PLANONLY           -- toggle display of query plan without executing
    SET SQL DIALECT <n>    -- set sql dialect to <n>
    SET STATs              -- toggle display of performance statistics
    SET TIME               -- toggle display of timestamp with DATE values
    SET TERM <string>      -- change statement terminator string
    SET WIDTH <col> [<n>]  -- set/unset print width to <n> for column <col>

All commands may be abbreviated to letters in CAPitals

Note	In the above, the `BLOB` commands only show the abbreviated form to save space, the full form is `BLOBdisplay`.In the following descriptions of the various `set` commands, we will use the full `BLOBdisplay` version of the appropriate commands.

The last line of the above output indicates that these commands can be abbreviated to the letters in capitals.

`SET`

The set command, without parameters, displays the current settings, as the following example from Firebird 4.0 shows:

SQL> set;
Print statistics:        OFF
Print per-table stats:   OFF
Echo commands:           OFF
List format:             OFF
Show Row Count:          OFF
Select maxrows limit:    0
Autocommit DDL:          ON
Access Plan:             OFF
Access Plan only:        OFF
Explain Access Plan:     OFF
Display BLOB type:       1
Column headings:         ON
Terminator:              ;
Time:                    OFF
Warnings:                ON
Bail on error:           OFF
Local statement timeout: 0
Keep transaction params: ON
    SET TRANSACTION

`SET HEADING`

SET HEADING [ON | OFF]

This command turns the display of column headings on or off as desired.If no parameter is supplied to the command, it toggles the current state of the heading display.

The heading display setting only affects the tabular display (list off) of query results.The list display (list on) always includes the column names.

SQL> set heading off;

SQL> select count(*) from employee;

          42

SQL> set heading on;

SQL> select count(*) from employee;

       COUNT
============
          42

`SET KEEP_TRAN_params`

Added in

Firebird 3.0.6 / 4.0

SET KEEP_TRAN_params [ON | OFF]

This command configures whether isql remembers the transaction configuration of the last SET TRANSACTION and applies it for implicitly started transactions.The default is ON in Firebird 4.0 and higher, and OFF in Firebird 3.0 (introduced in 3.0.6).If no parameter is supplied to the command, it toggles the current state of keep transaction parameters.

When set to ON, isql keeps the complete SQL text of the last successful SET TRANSACTION statement.New transactions are started — when started implicitly — using the same SQL text (instead of the default CONCURRENCY WAIT mode).When set to OFF, isql starts new transactions as usual.The name KEEP_TRAN can be used as a shorthand for KEEP_TRAN_PARAMS.

`SET LIST`

SET LIST [ON | OFF]

This command controls how the data returned by a select statement is displayed.The default setting is to display the data in tabular form with optional column headings at the top of each 'page'.Setting the list mode to ON results in a different format where each column heading is displayed on the left and the column data on the right.This repeats for each and every row returned by the query.

As with other commands, not providing a value to the command results in a toggle of the current setting.

SQL> set list off;

SQL> select emp_no, first_name, last_name, salary
CON> from employee;

 EMP_NO FIRST_NAME      LAST_NAME                           SALARY
======= =============== ==================== =====================
      2 Robert          Nelson                           105900.00
      4 Bruce           Young                             97500.00
      5 Kim             Lambert                          102750.00
      8 Leslie          Johnson                           64635.00
...

SQL> set list on;

SQL> select emp_no, first_name, last_name, salary
CON> from employee;

EMP_NO                          2
FIRST_NAME                      Robert
LAST_NAME                       Nelson
SALARY                          105900.00

EMP_NO                          4
FIRST_NAME                      Bruce
LAST_NAME                       Young
SALARY                          97500.00
...

`SET LOCAL_TIMEOUT`

Added in

Firebird 4.0

SET LOCAL_TIMEOUT timeout_value

The SET LOCAL_TIMEOUT configures a one-off statement timeout in milliseconds for the first statement executed after this SET LOCAL_TIMEOUT.

After statement execution, the timeout is automatically reset to zero.

Note	`SET LOCAL_TIMEOUT` is only available in `isql` for Firebird 4 or higher, and only when connecting to a Firebird 4 or higher database.

`SET NAMES`

SET NAMES [character_set]

This command defines the character set of subsequent database connections.If the default database character set is not NONE, then in situations where the client uses a different character set to the database, it is possible to suffer from data corruption as some character sets cannot convert some characters to a suitable character in another character set.

If you don’t pass a character set, the default will be to use the NONE character set.

You can determine a list of the valid character sets to use with the following query:

SQL> set width RDB$CHARACTER_SET_NAME 30;

SQL> select RDB$CHARACTER_SET_NAME
CON> from RDB$CHARACTER_SETS
CON> order by 1;

RDB$CHARACTER_SET_NAME
==============================
ASCII
...
WIN1258

`SET PER_TABle_stats`

Added in

Firebird 5.0

SET PER_TABle_stats [ON | OFF]

This command turns the display of per-table statistics on or off as desired.If no parameter is supplied to the command, it toggles the current state of the per-table statistics display.

When set to ON, isql shows per-table run-time statistics after query execution.It is set to OFF by default.This command is independent of the [isql-set-stats] command.The name PER_TABLE_STATS can be abbreviated up to PER_TAB.Tables in the output are sorted by their relation id’s.

Example (width reduced from original output):

-- check current value
SQL> SET;
...
Print per-table stats:   OFF
...

-- turn per-table stats on
SQL> SET PER_TABLE_STATS ON;
SQL> SELECT COUNT(*) FROM RDB$RELATIONS JOIN RDB$RELATION_FIELDS USING (RDB$RELATION_NAME);

                COUNT
=====================
534

Per table statistics:
--------------------+-------+-----+------+------+------+-------+-----+-------+
Table name          |Natural|Index|Insert|Update|Delete|Backout|Purge|Expunge|
--------------------+-------+-----+------+------+------+-------+-----+-------+
RDB$INDICES         |       |    3|      |      |      |       |     |       |
RDB$RELATION_FIELDS |       |  534|      |      |      |       |     |       |
RDB$RELATIONS       |     59|     |      |      |      |       |     |       |
RDB$SECURITY_CLASSES|       |    3|      |      |      |       |     |       |
--------------------+-------+-----+------+------+------+-------+-----+-------+

Note, some system tables are shown that were not listed in the query;the engine reads some additional metadata when preparing the query.

-- turn per-table stats off, using shortened name
SQL> SET PER_TAB OFF;

See also

[isql-set-stats]

`SET PLAN`

SET PLAN [ON | OFF]

This command determines whether isql displays the plan used to access the data for each statement executed.By default, ISQL does not display the plan.As with many other commands, not providing a parameter toggles the current state.

SQL> set plan on;

SQL> select emp_no, first_name, last_name
CON> from employee
CON> where emp_no = 107;

PLAN (EMPLOYEE INDEX (RDB$PRIMARY7))

 EMP_NO FIRST_NAME      LAST_NAME
======= =============== ====================
    107 Kevin           Cook

SQL> update employee
CON> set first_name = 'Norman'
CON> where last_name = 'Cook';

PLAN (EMPLOYEE INDEX (NAMEX))

SQL> select count(*) from employee;

PLAN (EMPLOYEE NATURAL)

       COUNT
============
          42

The execution plan is displayed before the output of a select statement.

See also

[isql-set-explain], [isql-set-planonly]

Effects of Various Plan-Related Commands

Usage options

SET PLAN: simple plan + query execution
SET PLANONLY: simple plan, no query execution
SET PLAN + SET EXPLAIN: explained plan + query execution
SET PLAN + SET EXPLAIN + SET PLANONLY: explained plan, no query execution
SET EXPLAIN: explained plan + query execution
SET EXPLAIN + SET PLANONLY: explained plan, no query execution

`SET PLANONLY`

SET PLANONLY [ON | OFF]

This command prevents isql from actually executing the SQL statement, and instead only shows the plan that would be used to access the data.This command relies on the [isql-set-plan] command.If set plan off had been executed, this command would have no effect, so turning planonly on has the additional effect of executing set plan on implicitly.Executing set planonly off does not implicitly execute set plan off.

SQL> set planonly on;

SQL> select count(*) from employee;

PLAN (EMPLOYEE NATURAL)

As before, not supplying a parameter toggles the current setting.

See also

[isql-set-explain], [isql-set-plan]

`SET SQLDA_DISPLAY`

Added in

Firebird 2.0

SET SQLDA_DISPLAY [ON | OFF]

This is a hidden command which is not mentioned in the output from the help set command.It displays internal details about the SQL statements being executed by isql.

SQL> set sqlda_display on;

SQL> select count(*) from employee;

INPUT message field count: 0

OUTPUT message field count: 1
01: sqltype: 580 INT64 scale: 0 subtype: 0 len: 8
  :  name: COUNT  alias: COUNT
  : table:   owner:

                COUNT
=====================
                   42

`SET SQL DIALECT`

SET SQL DIALECT {1 | 2 | 3}

This command specifies the Firebird SQL dialect to which the client session is to be changed.If the session is currently attached to a database of a different dialect to the one specified in the command, a warning is displayed.The values permitted are:

1 — which sets the client connection to SQL dialect 1
2 — which sets the client connection to SQL dialect 2.
3 — which sets the client connection to SQL dialect 3.

If executed before a CREATE DATABASE statement, it determines the dialect of the created database.

See [isql-dialects] for details of the differences between the three dialects.

SQL> set sql dialect 1;
WARNING: Client SQL dialect has been set to 1 when
connecting to Database SQL dialect 3 database.
...
SQL> set sql dialect 3;
SQL>

The warning in the above example has had to be split over two lines to fit on the page.Normally, it consists of a single line.

`SET AUTOddl`

SET AUTOddl [ON | OFF]

This command sets whether all DDL statements executed will be automatically committed or not.The command without any parameters acts as a toggle and turns autoddl off if it is currently on and vice versa.You may supply a specific parameter to make your intentions clear.The parameter must be one of on or off.The set command, with no parameters, will display the current setting.The default in isql is equivalent to set autoddl on.

`SET STATs`

SET STATs [ON | OFF]

This command determines whether isql displays various statistics about each SQL command executed.As usual, failing to pass a parameter results in the current setting being toggled.

This command is independent of the [isql-set-per-table-stats] command.

SQL> set stats on;

SQL> select count(*) from employee;

                COUNT
=====================
                   42

Current memory = 19570960
Delta memory = 0
Max memory = 19652528
Elapsed time = 0.001 sec
Buffers = 2048
Reads = 0
Writes = 0
Fetches = 48

See also

[isql-set-per-table-stats]

`SET TIME`

SET TIME [ON | OFF]

This command applies to dialect 1 databases only.It causes the time portion to be displayed or not, when the selected data is a column defined with the DATE data type.It has no effect in other dialects.

`SET TERM`

SET TERM new_terminator current_terminator

This command changes the statement terminator as defined by the provided string.This is mostly useful when you are about to enter a string of SQL statements making up a procedure, for example, or a trigger.With the default terminator, ;, isql would attempt to execute each statement when it sees a terminating semicolon, and given PSQL internally also uses semicolons, this would result in incomplete statements being executed.You need to change the terminator first, then enter the required code.When complete, you can change it back, but when doing so, you must remember to terminate the set term command with the current terminating character(s).

When first started, isql uses the semicolon (;) as the default terminator.

You can, if desired, simply change the terminator because you prefer something other than a semicolon.You don’t have to be writing PSQL code to change it.

SQL> -- Change terminator from ; to +
SQL> set term +;

SQL> select count(*) from employee+

       COUNT
============
          42

SQL> -- Change terminator from + to 'fred'
SQL> set term fred +

SQL> select count(*) from employee fred

       COUNT
============
          42

SQL> -- Change back from 'fred' to ;
SQL> set term ; fred

See the section on the terminator for full details.

`SET TRANSACTION`

This is not a hidden command which is not mentioned in the output from the help set command but a Firebird SQL statement.

There is a default transaction started for you when you use isql.When you commit or rollback in isql, the default transaction ends, and a new default transaction begins.These implicitly started transactions — by default — use the SET TRANSACTION defaults, which are:

READ WRITE — meaning that any SQL statement that is executed may make changes in the database.
WAIT — meaning that if a row in a table is currently locked by another session, the execution of the statement will wait until the other session either commits or rolls back.
SNAPSHOT — meaning that this transaction will be guaranteed a non-volatile view of the data and will be unaffected by any changes made and committed in any other transactions that take place while this one remains unfinished by a commit or rollback.

If [isql-set-keep-tran-params] is on, implicitly started transactions will use the last SET TRANSACTION statement executed.

A full explanation of transactions is beyond the scope of this manual.For more information see the Firebird Language Reference for your Firebird version, or The Firebird Book by Helen Borrie.

For example, see SET TRANSACTION in the Firebird 5.0 Language Reference.

`SET WARNINGS` or `SET WNG`

SET {WARNINGS | WNG} [ON | OFF]

This command specifies whether warnings are to be output.A few examples for which isql issues warnings are:

SQL statements with no effect.
Pending database shutdown.
API calls that may be replaced in future versions of Firebird.
Expressions that may cause differing results in different versions of Firebird.
Connecting to a database with a connection dialect different from the database dialect.
In Firebird 1.0, SQL statements with ambiguous join specifications.More recent Firebird versions will raise an exception rather than a warning.

As with many of the set commands, set warnings acts as a toggle if no parameter is supplied.

`SET WIDTH`

Normally the width of a character column in a table defines the width of the output when that column is selected.Using the set width command allows the user to define a wider or narrower output column width.

The format of the command is:

SET WIDTH column_or_alias [width]

The setting remains until changed to a new width, or until cancelled by the set width column_or_alias command;no width supplied means use the default width setting for this column.

The following example shows the width of the last_name column being amended.The first SELECT shows the default setting which is a width of 20 characters (count the '=' in the headings) which is the definition of the last_name column in the employee table.The second shows the width being reduced to 10 characters.

SQL> select first 10 emp_no, last_name
CON> from employee
CON> order by last_name;

 EMP_NO LAST_NAME
======= ====================
     34 Baldwin
    105 Bender
     28 Bennet
     83 Bishop
    109 Brown

SQL> set width last_name 10;

SQL> select first 10 emp_no, last_name
CON> from employee
CON> order by last_name;

 EMP_NO LAST_NAME
======= ==========
     34 Baldwin
    105 Bender
     28 Bennet
     83 Bishop
    109 Brown

EMP_NO is a smallint data type.Unfortunately, it’s not possible to change the width on non-character columns like integer, smallint etc.The set width emp_no 10; command, for example, has no effect, as shown below, which also demonstrates turning off a previous width setting for the last_name column:

SQL> set width last_name;

SQL> set width emp_no 10;

SQL> select first 10 emp_no, last_name
CON> from employee
CON> order by last_name;

 EMP_NO LAST_NAME
======= ====================
     34 Baldwin
    105 Bender
     28 Bennet
     83 Bishop
    109 Brown

`SET BAIL`

SET BAIL [ON | OFF]

This command determines if isql will "bail out" on any errors when the input command has been used to read a script file.Isql will not exit if it is running in interactive mode, and you cause an error.

Executing this command, without passing a parameter, results in a toggling of the current state.If bail is on, it will turn off and vice versa.

`SET BLOBdisplay`

SET BLOBdisplay [n | ALL | OFF]

This command determines if BLOB column data is displayed in the output when a table with BLOB columns is queried.The default for this command, if no parameters are passed, is to set BLOB data off — it will not be displayed, only the blob id will be shown.

The blob id is discussed above in the section describing the [isql-command-blobdump] and [isql-command-blobview] commands.

If ALL is passed, then all BLOB sub-types will be displayed.

If a number representing the blob subtype is passed, then only BLOBs with the specific subtype will be displayed.The default is 1 for text subtypes.

SQL> -- Don't display any blob data.
SQL> set blob off;

SQL> select proj_desc
CON> from project
CON> where proj_id = 'HWRII';

        PROJ_DESC
=================
             85:e


SQL> -- Display all blob data.
SQL> set blobdisplay all;

SQL> select proj_desc
CON> from project
CON> where proj_id = 'HWRII';

        PROJ_DESC
=================
             85:e
==============================================================================
PROJ_DESC:
Integrate the hand-writing recognition module into the
universal language translator.
==============================================================================

SQL> -- Only display type 1 blob data = text.
SQL> set blob 1;

SQL> select proj_desc
CON> from project
CON> where proj_id = 'HWRII';

        PROJ_DESC
=================
             85:e
==============================================================================
PROJ_DESC:
Integrate the hand-writing recognition module into the
universal language translator.
==============================================================================

SQL> -- Only display blob type 7 = not text!
SQL> set blob 7;

SQL> select proj_desc
CON> from project
CON> where proj_id = 'HWRII';

        PROJ_DESC
=================
             85:e
==============================================================================
PROJ_DESC:
BLOB display set to subtype 7. This BLOB: subtype = 1
==============================================================================

You will notice in the last example that a message was displayed advising that we are only displaying BLOB data for subtype 7 and the BLOB data in this table is a subtype 1, so the data is not displayed.

`SET COUNT`

SET COUNT [ON | OFF]

This command determines whether a line of text is displayed at the end of the output from a DML statement, telling the user how many rows were affected.

SQL> set count on;

SQL> select count(*) from employee;

       COUNT
============
          42

Records affected: 1

The record count is displayed for all DML operations, not just for a SELECT.

SQL> create table fred( a integer);
SQL> commit;

SQL> insert into fred values (666);
Records affected: 1

SQL> update fred set a = 123 where a = 666;
Records affected: 1

SQL> delete from fred;
Records affected: 1

SQL> commit;

`SET MAXROWS` or `SET ROWCOUNT`

SET {MAXROWS | ROWCOUNT} [n]

Setting maxrows to zero, which is the default when isql is started, results in a select statement returning all rows which meet the criteria in the where clause.There are circumstances where you do not want lots and lots of output scrolling up the screen, so you may set maxrows to a smaller number and all subsequent select statements will only display the first n rows instead of everything.

Note	In older versions of `isql`, only `set rowcount` is available.

SQL> set count on;
SQL> set maxrows 0;

SQL> select emp_no from employee;

 EMP_NO
=======
      2
      4
...
    144
    145

Records affected: 42

SQL> set maxrows 10;
SQL> select emp_no from employee;

 EMP_NO
=======
      2
      4
...
     15
     20

Records affected: 10

There is no indication that maxrows is restricting the number of rows returned.It is the responsibility of the user to remember, or check whether maxrows is on or off.Using maxrows can lead to confusion about exactly how many rows there are in a table!

`SET ECHO`

SET ECHO [ON | OFF]

This command causes executed SQL commands to be displayed on the output device prior to their execution.You may wish to turn echo off as part of a script file.The isql default is for echo to be off.The command without any parameters acts as a toggle and turns echo on if it is currently off and vice versa.

SQL> set echo on;

SQL> select count(*) from rdb$database;
select count(*) from rdb$database;

       COUNT
============
           1

SQL> set echo off;
set echo off;

SQL> select count(*) from rdb$database;

       COUNT
============
           1

This command can be handy in a script file.If you receive an error, it can sometimes be difficult to determine the exact SQL statement that caused it.If you set echo on in your script, you will at least be able to determine exactly which statement failed.

`SET EXEC_PATH_DISPLAY`

Added in

Firebird 4.0.1

SET EXEC_PATH_DISPLAY [BLR | OFF]

Retrieves the execution path of a DML statement formatted as BLR (Binary Language Representation) text.

It requires a Firebird 4.0.1 server or greater to work.

Warning

This feature is closely tied to engine internals and its usage is discouraged if you do not understand very well how these internals are subject to change between versions.

`SET EXPLAIN`

Added in

Firebird 3.0

SET EXPLAIN [ON | OFF]

This command extends the [isql-set-plan] option to report the explained plan instead of the standard one.

If plan output is not currently enabled, then set explain on turns the plan output on.

SQL> set explain on;

SQL> select emp_no, first_name, last_name
CON> from employee
CON> where emp_no = 107;

Select Expression
    -> Filter
        -> Table "EMPLOYEE" Access By ID
            -> Bitmap
                -> Index "RDB$PRIMARY7" Unique Scan

 EMP_NO FIRST_NAME      LAST_NAME
======= =============== ====================
    107 Kevin           Cook

See also

[isql-set-plan], [isql-set-planonly]

`Isql` Show commands

As explained in [isql-commands], there are a number of individual show commands within isql.The general format of the show commands is:

SHOW [<object> [name]]

The object is always required, and the name is required to display details of a specific object.Without a name, the commands will usually display all objects of the requested type.

Unfortunately, unlike the set commands, there is no handy drill down into the various show commands using the help command.However, if you execute show on its own, you will be given a little more assistance.For example, isql of Firebird 4.0 shows:

SQL> show;
Valid options are:
CHECKs                   COMMENTs                 COLLATEs
COLLATIONs               DOMAINs                  DB
DATABASE                 DEPENdency               DEPENdencies
EXCEPtions               FILTERs                  FUNCtions
GENerators               GRANTs                   INDexes
INDICES                  MAPping                  PROCedures
PACKages                 PUBlications             ROLEs
SYStem                   SEQuences                SECURITY CLAsses
SECCLAsses               SCHEmas                  TABLEs
TRIGgers                 USERS                    VIEWs
Command error: show

The upper case letters indicate what you must type as an absolute minimum.

The show commands are detailed and described below.Where possible, examples from the employee database are shown.

`SHOW CHECKs`

SHOW CHECKs table_name

This command displays all user-defined check constraints defined for a specific table.Unlike other show commands, there is no option to display a list of all check constraints in the database.You must always provide a table name as part of the command.

SQL> show check employee;
CONSTRAINT INTEG_30:
  CHECK ( salary >= (SELECT min_salary FROM job WHERE
                        job.job_code = employee.job_code AND
                        job.job_grade = employee.job_grade AND
                        job.job_country = employee.job_country) AND
            salary <= (SELECT max_salary FROM job WHERE
                        job.job_code = employee.job_code AND
                        job.job_grade = employee.job_grade AND
                        job.job_country = employee.job_country))

`SHOW GENerators`

SHOW {GENerators | SEQuences} [name]

SHOW GENerators and [isql-show-sequences] are identical.Generators are the old Firebird term for what are more commonly known as sequences in the SQL standard and other databases.You are encouraged to use the term sequence rather than generator, but isql considers them aliases.

The first form of the commands above list all user-defined sequences in the current database, while the second form displays details of a specific sequence.

SQL> show sequences;
Generator CUST_NO_GEN, current value: 1015, initial value: 1, increment: 1
Generator EMP_NO_GEN, current value: 145, initial value: 1, increment: 1

SQL> show sequence emp_no_gen;
Generator EMP_NO_GEN, current value: 145, initial value: 1, increment: 1

`SHOW GRANTs`

SHOW GRANTs [{object_name | role_name}]

This command displays a list of all grants in the current database if the first form of the command is used.The second form drills down and displays only those details for the selected object, which may be a table, procedure, etc.Alternatively, if a role name is provided, only a list of users who have been granted that role will be displayed.

SQL> show grants;

/* Grant permissions for this database */
GRANT ALL ON COUNTRY TO PUBLIC WITH GRANT OPTION
GRANT ALL ON CUSTOMER TO PUBLIC WITH GRANT OPTION
...
GRANT EXECUTE ON PROCEDURE ADD_EMP_PROJ TO PUBLIC WITH GRANT OPTION
GRANT EXECUTE ON PROCEDURE ALL_LANGS TO PUBLIC WITH GRANT OPTION
...

SQL> show grants employee;
GRANT ALL ON EMPLOYEE TO PUBLIC WITH GRANT OPTION

SQL> show grants ship_order;
GRANT EXECUTE ON PROCEDURE SHIP_ORDER TO PUBLIC WITH GRANT OPTION

SQL> show grants default_user;
GRANT DEFAULT_USER TO SYSDBA

`SHOW INDexes` or `SHOW INDICES`

SHOW {INDexes | INDICES} [{table_name | index_name}]

You may specify either indexes (or abbreviated forms starting with ind) or indices, they are treated as aliases by isql.The first form of this command lists all user-defined indices in the current database.The second form of the command lists the indices of a specific table as determined by the table_name parameter.The final form of the command displays details of a specific index.

SQL> show indices;
RDB$PRIMARY1 UNIQUE INDEX ON COUNTRY(COUNTRY)
CUSTNAMEX INDEX ON CUSTOMER(CUSTOMER)
...
SALESTATX INDEX ON SALES(ORDER_STATUS, PAID)

SQL> show indices employee;
NAMEX INDEX ON EMPLOYEE(LAST_NAME, FIRST_NAME)
RDB$FOREIGN8 INDEX ON EMPLOYEE(DEPT_NO)
RDB$FOREIGN9 INDEX ON EMPLOYEE(JOB_CODE, JOB_GRADE, JOB_COUNTRY)
RDB$PRIMARY7 UNIQUE INDEX ON EMPLOYEE(EMP_NO)

SQL> show index namex;
NAMEX INDEX ON EMPLOYEE(LAST_NAME, FIRST_NAME)

`SHOW MAPping`

Added in

Firebird 3.0

SHOW MAPping [name]

This command shows the authentication mapping rules defined in this database or in the security database.

SQL> show mapping;

WIN_ADMINS USING PLUGIN WIN_SSPI FROM PREDEFINED_GROUP DOMAIN_ANY_RID_ADMINS TO ROLE RDB$ADMIN

*** Global mapping ***
WIN_ADMINS_GLOBAL USING PLUGIN WIN_SSPI FROM PREDEFINED_GROUP DOMAIN_ANY_RID_ADMINS TO ROLE RDB$ADMIN

SQL> show mapping WIN_ADMINS;

WIN_ADMINS USING PLUGIN WIN_SSPI FROM PREDEFINED_GROUP DOMAIN_ANY_RID_ADMINS TO ROLE RDB$ADMIN

`SHOW PROCedures`

SHOW PROCedures [name]

This command lists all user-defined procedures created in the current database.The second form of the command shows the details and source code for a specific procedure.See also the [isql-show-functions] and [isql-show-triggers] commands.

SQL> show procedures;
ADD_EMP_PROJ; Dependencies: EMPLOYEE_PROJECT (Table), UNKNOWN_EMP_ID (Exception)
ALL_LANGS; Dependencies: JOB (Table), SHOW_LANGS (Procedure)

SQL> show procedure all_langs;
Procedure text:
=============================================================================
BEGIN
        FOR SELECT job_code, job_grade, job_country FROM job
                INTO :code, :grade, :country

        DO
        BEGIN
            FOR SELECT languages FROM show_langs
                    (:code, :grade, :country) INTO :lang DO
                SUSPEND;
            /* Put nice separators between rows */
            code = '=====';
            grade = '=====';
            country = '===============';
            lang = '==============';
            SUSPEND;
        END
    END
=============================================================================
Parameters:
CODE                              OUTPUT VARCHAR(5)
GRADE                             OUTPUT VARCHAR(5)
COUNTRY                           OUTPUT VARCHAR(15)
LANG                              OUTPUT VARCHAR(15)

Since Firebird 5.0, isql lists procedures and packaged procedures in the same way, where the latter are displayed in the form <package-name>.<procedure-name>.Isql of Firebird 3.0 and 4.0 displayed procedures and packaged procedures differently.

`SHOW PACKages`

Added in

Firebird 3.0

SHOW PACKages [name]

This command lists all user-defined packages in the current database if the first form is used, or drills down to display the definition of the package.

SQL> show packages;
TEST

SQL> show package test;
TEST
Header source:
BEGIN
  PROCEDURE P1(I INT) RETURNS (O INT); -- public procedure
END

Body source:
BEGIN
  FUNCTION F1(I INT) RETURNS INT; -- private function
  PROCEDURE P1(I INT) RETURNS (O INT)
  AS
  BEGIN
  END
  FUNCTION F1(I INT) RETURNS INT
  AS
  BEGIN
    RETURN 0;
  END
END

`SHOW PUBlications`

Added in

Firebird 5.0

SHOW PUBlications [name]

This command lists all user-defined publications in the current database if the first form is used, or drills down to display the definition of the publication.

Currently, Firebird only has one system-defined publication, RDB$DEFAULT, and no option to create user-defined publications, so the output of show publications is always the same:

SQL> show publications;
There is no publications in this database

SQL> show system publications;
RDB$DEFAULT

SQL> show publication rdb$default;
RDB$DEFAULT: Disabled

`SHOW ROLEs`

SHOW ROLEs [name]

This command lists all roles in the current database if the first form is used, or drills down to display a list of all users who have been granted a specific role if the second form of the command is used.

SQL> show roles;
DEFAULT_USER

SQL> show role default_user;
Role DEFAULT_USER is granted to:
SYSDBA

`SHOW SECCLAsses`

SHOW SECCLAsses object_name

This command displays details about the security classes for a given object.The object_name passed to the command need not be a table name, the command works for tables, procedures, etc.

SQL> show secclasses employee;
Table's main sec class SQL$466
Table's default sec class SQL$DEFAULT58

`SHOW SECURITY CLAsses`

Although this command is listed in the output of SHOW;, it is not actually available.Use [isql-show-secclasses].

`SHOW COLLATIONs` or `SHOW COLLATEs`

Added in

Firebird 2.0

SHOW {COLLATIONs | COLLATEs} [name]

These commands display a list of all user-defined collations in the current database.The first form of the commands display a list of all collations while a specific collation may be displayed by providing the collation name.

SQL> show collations;
UNICODE_ENUS_CI, CHARACTER SET UTF8, FROM EXTERNAL ('UNICODE'), PAD SPACE,
CASE INSENSITIVE, 'COLL-VERSION=58.0.6.48'
UNICODE_ENUS_CS, CHARACTER SET UTF8, FROM EXTERNAL ('UNICODE'), PAD SPACE,
'COLL-VERSION=58.0.6.48'

SQL> show collation unicode_enus_ci;
UNICODE_ENUS_CI, CHARACTER SET UTF8, FROM EXTERNAL ('UNICODE'), PAD SPACE,
CASE INSENSITIVE, 'COLL-VERSION=58.0.6.48'

You can see from the output above, which is not part of the employee database, does appear to display all relevant information in the first form of the command.There does not appear to be much reason to drill down into a specific collation — at least, not for to this example.Some lines in the above have had to be split over two to allow it to fit on the page.

`SHOW SEQuences`

The Firebird specific name, generator, has been updated to match the SQL standard term sequence.The show sequences command is identical to [isql-show-generators] (above) and the output is identical.

`SHOW SQL DIALECT`

SHOW SQL DIALECT

This command shows the dialect of the current database as well as the dialect of the current connection.

SQL> show SQL Dialect;
        Client SQL dialect is set to: 3 and database SQL dialect is: 3

`SHOW SYStem`

SHOW SYStem [<object_type>]

<object_type> :: =
  { TABLEs | COLLATIONs | COLLATEs | ROLEs
  | FUNCtions | PROCedures | PACKages | PUBLications }

This command lists the internal, i.e. system, objects created and used in the current database.The optional parameter restricts the listing to show only the specified object type.This applies from Firebird 2.0 onwards.Prior to version 2.0, the command would only list the system tables — equivalent to the show system tables command.

If no parameter is passed, the listing will display tables, functions (not built-in functions though), collations, roles, procedures, packages, and publications.

Types PROCedures, PACKages and PUBLications are available since Firebird 5.0.

SQL> show system;
Tables:
MON$ATTACHMENTS
...

Functions:
RDB$BLOB_UTIL.IS_WRITABLE
...

Procedures:
RDB$BLOB_UTIL.CANCEL_BLOB
...

Packages:
RDB$BLOB_UTIL
...

Collations:
ASCII
...

Roles:
RDB$ADMIN

Publications:
RDB$DEFAULT

Note that packaged procedures and functions are listed as <package-name>.<routine-name>.

The show system <object_type> can sometimes show more details compared to just show system:

SQL> show system collations;
ASCII, CHARACTER SET ASCII, PAD SPACE, SYSTEM
...
WIN_PTBR, CHARACTER SET WIN1252, PAD SPACE, CASE INSENSITIVE, ACCENT INSENSITIVE, SYSTEM

If you wish to drill down and display details of a specific object, use the corresponding show <object-type> name command, without system.

SQL> show table mon$io_stats;
MON$STAT_ID                     (RDB$STAT_ID) INTEGER Nullable
MON$STAT_GROUP                  (RDB$STAT_GROUP) SMALLINT Nullable
MON$PAGE_READS                  (RDB$COUNTER) BIGINT Nullable
MON$PAGE_WRITES                 (RDB$COUNTER) BIGINT Nullable
MON$PAGE_FETCHES                (RDB$COUNTER) BIGINT Nullable
MON$PAGE_MARKS                  (RDB$COUNTER) BIGINT Nullable

SQL> show collation ascii;
ASCII, CHARACTER SET ASCII, PAD SPACE, SYSTEM

`SHOW SCHEmas`

Added in

Firebird 3.0

SHOW SCHEmas

This command always returns an error.

SQL> show schemas;
Command error: show schemas

`SHOW TABLEs`

SHOW TABLEs [name]

This command lists all user-defined tables in the database if the first form of the command is used, or displays the columns and data types or domains of the table if the second form is used.

SQL> show tables;
COUNTRY
CUSTOMER
...

SQL> show table country;
COUNTRY                         (COUNTRYNAME) VARCHAR(15) Not Null
CURRENCY                        VARCHAR(10) Not Null
CONSTRAINT INTEG_2:
  Primary key (COUNTRY)

You will note that if there are comments defined for a table, this command will not display them.You must use the [isql-show-comments] command, but be aware that you will then be given all comments in the database.There is no command to extract the comments for a single object, unless you query the system tables directly.

SQL> comment on table country is 'This table holds details about countries.';
SQL> commit;

SQL> show comments;
...
COMMENT ON TABLE COUNTRY IS This table holds details about countries.;
...

SQL> show table country;
COUNTRY                         (COUNTRYNAME) VARCHAR(15) Not Null
CURRENCY                        VARCHAR(10) Not Null
CONSTRAINT INTEG_2:
  Primary key (COUNTRY)

SQL> select rdb$description
CON> from rdb$relations
CON> where rdb$relation_name = 'COUNTRY';

  RDB$DESCRIPTION
=================
            6:1e7
==============================================================================
RDB$DESCRIPTION:
This is a table holding details about countries.
==============================================================================

The output from the final query above is not ideal, but at least it’s much less displayed information when there are lots of comments in your database.

`SHOW TRIGgers`

SHOW TRIGgers [name]

This command lists all user-defined triggers in the current database.The second form of the command shows the details and source code for a specific trigger.See also the [isql-show-procedures] and [isql-show-functions] commands.

SQL> show triggers;
SET_CUST_NO; Table: CUSTOMER
SAVE_SALARY_CHANGE; Table: EMPLOYEE
SET_EMP_NO; Table: EMPLOYEE
POST_NEW_ORDER; Table: SALES

SQL> show trigger set_cust_no;

Triggers on Table CUSTOMER:
SET_CUST_NO, Sequence: 0, Type: BEFORE INSERT, Active
Trigger text:
=============================================================================
AS
BEGIN
    if (new.cust_no is null) then
    new.cust_no = gen_id(cust_no_gen, 1);
END
=============================================================================

`SHOW VERsion`

SHOW VERsion

This command displays details about the Firebird software, your database and the on-disk structure (ODS) in use.

SQL> show version;
ISQL Version: WI-V5.0.0.1306 Firebird 5.0
Server version:
Firebird/Windows/AMD/Intel/x64 (access method), version "WI-V5.0.0.1306 Firebird 5.0"
on disk structure version 13.1

Depending on the connection protocol, the output may include multiple version lines.The example above is an embedded connection, so only the database engine information is shown.

`SHOW USERS`

SHOW USERS

This command shows a list of users in the security database, and the number of connections they have to the current database.

Note	Older versions of `isql` show only connected users, and will report each connection separately.

SQL> show users;
Users in the database
  1  NORMAN
  8 #SYSDBA

Only users with administrator privileges will be able to see information on other users.

`SHOW VIEWs`

SHOW VIEWs [name]

The first form of this command displays a list of all views in the current database.Drilling down using the second form of the command will display the columns and source code for a specific view.

SQL> show views;
PHONE_LIST

SQL> show view phone_list;
EMP_NO                          (EMPNO) SMALLINT Not Null
FIRST_NAME                      (FIRSTNAME) VARCHAR(15) Not Null
LAST_NAME                       (LASTNAME) VARCHAR(20) Not Null
PHONE_EXT                       VARCHAR(4) Nullable
LOCATION                        VARCHAR(15) Nullable
PHONE_NO                        (PHONENUMBER) VARCHAR(20) Nullable
View Source:
==== ======
SELECT
    emp_no, first_name, last_name, phone_ext, location, phone_no
    FROM employee, department
    WHERE employee.dept_no = department.dept_no

`SHOW COMMENTs`

SHOW COMMENTs

This command displays all comments that have been created, on various objects, in the current database.There is no option to display a specific comment.Each comment is listed along with the object type and name, to which it has been applied.

SQL> show comments;
COMMENT ON DATABASE IS This is the demonstration EMPLOYEE database.;
COMMENT ON TABLE EMPLOYEE IS The EMPLOYEE table has details of our employees.;

The actual comment text is shown between the word 'IS' and the trailing semicolon.

`SHOW DATABASE` or `SHOW DB`

SHOW {DATABASE | DB}

The show database (or show db) command displays details about the current database.The ODS version, shown in the following examples, is only displayed from Firebird version 2.0 onwards, and other options depend on the type of connection and the Firebird version.

SQL> show database;
Database: employee
        Owner: SYSDBA
PAGE_SIZE 8192
Number of DB pages allocated = 346
Number of DB pages used = 319
Number of DB pages free = 27
Sweep interval = 20000
Forced Writes are OFF
Transaction - oldest = 236
Transaction - oldest active = 237
Transaction - oldest snapshot = 237
Transaction - Next = 244
ODS = 13.1
Database not encrypted
Embedded connection
Creation date: Jan 11, 2024 12:08:41
Replica mode: NONE
Default Character set: NONE
Publication: Disabled

No parameters, such as a specific database name, are required and if supplied, will be ignored.The details displayed will always be for the current database.

SQL> show database testing_db;
Database: employee
        Owner: SYSDBA
PAGE_SIZE 8192
...
Publication: Disabled

You will note from the above that the details displayed are still for the employee database.

`SHOW DEPENdencies` or `SHOW DEPENdency`

SHOW {DEPENdencies | DEPENdency} object_name

These commands display all dependencies for the specified object name supplied as a parameter.The object name supplied need not necessarily be a table name, it could be a function or procedure name, a sequence name etc.

The output listed is a comma-separated list of the other objects in the database upon which the supplied object is dependent.In other words, a procedure would fail to compile if any of the listed dependencies was to be removed, for example.

SQL> show dependencies SET_CUST_NO;
        [SET_CUST_NO:Trigger]
CUSTOMER:Table<-CUST_NO, CUST_NO_GEN:Generator
+++

The listing above shows that SET_CUST_NO is a trigger and that it is dependent on two separate objects, the CUST_NO column of table CUSTOMER, and the sequence (generator) named CUST_NO_GEN.If you display the trigger itself, you will see both of those objects mentioned:

SQL> show trigger set_cust_no;

Triggers on Table CUSTOMER:
SET_CUST_NO, Sequence: 0, Type: BEFORE INSERT, Active
Trigger text:
=============================================================================
AS
BEGIN
    if (new.cust_no is null) then
    new.cust_no = gen_id(cust_no_gen, 1);
END
=============================================================================

Sometimes, the output can be a little confusing.You may see various objects in the list that don’t appear to be relevant.The RDB$DEPENDENCIES table, where the data comes from, also holds details of system objects upon which a given object will depend.

`SHOW DOMAINs`

SHOW DOMAINs [name]

This command displays domain information.A domain is a user-defined data type, global to the database.It is used to define the format and range of columns, upon which the actual column definitions in tables are based.

Firebird tables are defined by the specification of columns, which store appropriate information in each column using data types.

A data type is an elemental unit when defining data, which specifies the type of data stored in tables, and which operations may be performed on this data.It can also include permissible calculative operations and maximum data size.Examples of data types include: numerical (numeric, decimal, integer), textual (char, varchar, nchar, nvarchar), date (date, time, timestamp) and blobs (binary large objects).

As with many show commands, there are two forms.The first displays a list of all known user-defined domains in the database while the second allows you to display the details of a specific domain.

SQL> show domain;
ADDRESSLINE
BUDGET
...

SQL> show domain addressline;
ADDRESSLINE                     VARCHAR(30) Nullable

`SHOW EXCEPtions`

SHOW EXCEPtions [name]

This command displays all user-defined exceptions in the current database.Details of the exception’s error message and objects which use the exception — those which are dependant upon the exception — are also shown.You may display individual exception’s details with the second form of the command.

SQL> show exceptions;
CUSTOMER_CHECK; Msg: Overdue balance -- can not ship.; Used by: SHIP_ORDER (Stored procedure)
CUSTOMER_ON_HOLD; Msg: This customer is on hold.; Used by: SHIP_ORDER (Stored procedure)
...

SQL> show exception customer_on_hold;
CUSTOMER_ON_HOLD; Msg: This customer is on hold.; Used by: SHIP_ORDER (Stored procedure)

`SHOW FILTERs`

SHOW FILTERs [name]

This command displays a list of all user-defined BLOB filters declared in the current database using the declare filter command.The second form of the command shows the full details of a specific filter.

SQL> show filter;
FUNNEL
...

SQL> show filter funnel;
BLOB Filter: FUNNEL
        Input subtype: 2 Output subtype: 1
        Filter library is myfilterlib
        Entry point is blr2asc

`SHOW FUNCtions`

SHOW FUNCtions [name]

This command lists all user-defined external and stored functions declared in the current database.External functions are those defined and coded in various UDF libraries.

The second form of the command shows the details of a specific function.

SQL> show functions;
ADDDAY
ADDHOUR
...

SQL> show function addyear;

Function ADDYEAR:
Function library is fbudf
Entry point is addYear
Returns  TIMESTAMP
Argument 1: TIMESTAMP
Argument 2: INTEGER

Since Firebird 5.0, isql lists functions and packaged functions in the same way, where the latter are displayed in the form <package-name>.<function-name>.Isql of Firebird 3.0 and 4.0 displayed functions and packaged functions differently.

Document History

The exact file history is recorded in the firebird-documentation git repository; see https://github.com/FirebirdSQL/firebird-documentation

Revision History

Revision History
1.4	4 May 2024	MR	Wrong name for `SET` option `EXEC_DISPLAY_PATH` should be `EXEC_PATH_DISPLAY` (#209)
1.3	2 Apr 2024	MR	Protocol names are lowercase (#205)
1.2	24 Feb 2024	Replaced `isql -⁠help` (invalid switch) with `isql -⁠?` (valid switch) Added word-joiner in commandline switches between minus (`-`) and first character to ensure they aren’t broken up on word wrap Include `isql` name in the document title, making it the same as on https://firebirdsql.org/en/reference-manuals/	1.1
17 Jan 2024	MR	Misc. copy-editing Moved `SET KEEP_TRAN_params` for correct alphabetical ordering Replaced Firebird 4.0 Language Reference link with Firebird 5.0 Language Reference link Documented `SET PER_TABle_stats` introduced in Firebird 5.0.Adapted from the original text by Vlad Khorsun in `docs/README.isql_enhancements.txt`. Documented new options for `SHOW SYStem` Documented `SHOW PUBlications` Replaced (most) output examples with output of Firebird 5.0 Removed `SQL>` prefix and `;` terminator from syntax documentation	1.0
24 Dec 2021	MR	Reversed order of this document history to put the most recent change first Documented `SET EXEC_PATH_DISPLAY` introduced in Firebird 4.0.1.Adapted from the original text by Adriano dos Santos Fernandes in `docs/README.isql_enhancements.txt`.	0.9
12 Jun 2021	MR	Fixed wrong scope of `SET NAMES` (firebird-documentation#153) Documented connection strings (firebird-documentation#110) Add link to Firebird 4.0 Language Reference for `CREATE DATABASE` syntax	0.8
24 May 2021	MR	Added missing Firebird 3.0 and 4.0 features (`SET MAXROWS`, `SET EXPLAIN`, `SET KEEP_TRAN_PARAMS`, `SHOW MAPPING`, `SHOW PACKAGES`, `SHOW SCHEMAS`) Used consistent code formatting in section titles of commands Added command aliases to section titles Updated example output of most commands with output of Firebird 4.0 General copy-editing	0.7
08 May 2021	MR	Documented `SET LOCAL_TIMEOUT`	0.6
20 Jun 2020	MR	Conversion to AsciiDoc, minor copy-editing	0.5
10 Apr 2012	ND	More tidying up.Plus: `Show` commands removed to a separate section. `Set` commands moved to a separate section. The Command Line Switches section relocated to a better place. The section Ending an Isql Session was relocated to a better place.	0.4
15 Feb 2012	ND	General tidy up.Changes to formatting.Corrected some Docbook "misuse".Spelling & punctuation corrections.Lists compacted.Corrected <screen> overflow in pdf rendering.Etc.	0.3
20 Oct 2009	ND	Converted from a chapter in the Command Line Utilities manual to stand alone manual in its own right. Changed title to Firebird Interactive SQL Utility to bring it in line with the other utility manuals. Many other updates to bring this manual into line with the others and to incorporate Firebird 2 changes etc.	0.2
5 Jul 2008	PV	Changed title to Isql - Firebird Interactive SQL Utility to bring it in line with the other manuals.Added `titleabbrev` and edition info.Moved Audience and Version sections into Introduction.Removed Related Documentation section.Fixed typos, interpunction (still more to do here).Replaced most `emphasis`es and all `citetitle`s with more appropriate tags.Gave IDs to manual and all (sub)sections.Added manual History and License Notice.	0.1

1.4

4 May 2024

Wrong name for SET option EXEC_DISPLAY_PATH should be EXEC_PATH_DISPLAY (#209)

1.3

2 Apr 2024

Protocol names are lowercase (#205)

1.2

24 Feb 2024

Replaced isql -⁠help (invalid switch) with isql -⁠? (valid switch)
Added word-joiner in commandline switches between minus (-) and first character to ensure they aren’t broken up on word wrap
Include isql name in the document title, making it the same as on https://firebirdsql.org/en/reference-manuals/

1.1

17 Jan 2024

Misc. copy-editing
Moved SET KEEP_TRAN_params for correct alphabetical ordering
Replaced Firebird 4.0 Language Reference link with Firebird 5.0 Language Reference link
Documented SET PER_TABle_stats introduced in Firebird 5.0.Adapted from the original text by Vlad Khorsun in docs/README.isql_enhancements.txt.
Documented new options for SHOW SYStem
Documented SHOW PUBlications
Replaced (most) output examples with output of Firebird 5.0
Removed SQL> prefix and ; terminator from syntax documentation

1.0

24 Dec 2021

Reversed order of this document history to put the most recent change first
Documented SET EXEC_PATH_DISPLAY introduced in Firebird 4.0.1.Adapted from the original text by Adriano dos Santos Fernandes in docs/README.isql_enhancements.txt.

0.9

12 Jun 2021

Fixed wrong scope of SET NAMES (firebird-documentation#153)
Documented connection strings (firebird-documentation#110)
Add link to Firebird 4.0 Language Reference for CREATE DATABASE syntax

0.8

24 May 2021

Added missing Firebird 3.0 and 4.0 features (SET MAXROWS, SET EXPLAIN, SET KEEP_TRAN_PARAMS, SHOW MAPPING, SHOW PACKAGES, SHOW SCHEMAS)
Used consistent code formatting in section titles of commands
Added command aliases to section titles
Updated example output of most commands with output of Firebird 4.0
General copy-editing

0.7

08 May 2021

Documented SET LOCAL_TIMEOUT

0.6

20 Jun 2020

Conversion to AsciiDoc, minor copy-editing

0.5

10 Apr 2012

More tidying up.Plus:

Show commands removed to a separate section.
Set commands moved to a separate section.
The Command Line Switches section relocated to a better place.
The section Ending an Isql Session was relocated to a better place.

0.4

15 Feb 2012

General tidy up.Changes to formatting.Corrected some Docbook "misuse".Spelling & punctuation corrections.Lists compacted.Corrected <screen> overflow in pdf rendering.Etc.

0.3

20 Oct 2009

Converted from a chapter in the Command Line Utilities manual to stand alone manual in its own right.

Changed title to Firebird Interactive SQL Utility to bring it in line with the other utility manuals.

Many other updates to bring this manual into line with the others and to incorporate Firebird 2 changes etc.

0.2

5 Jul 2008

Changed title to Isql - Firebird Interactive SQL Utility to bring it in line with the other manuals.Added titleabbrev and edition info.Moved Audience and Version sections into Introduction.Removed Related Documentation section.Fixed typos, interpunction (still more to do here).Replaced most emphasises and all citetitles with more appropriate tags.Gave IDs to manual and all (sub)sections.Added manual History and License Notice.

0.1

Overview

The isql utility is a text-mode client tool located in the bin directory of the Firebird installation.It provides a commandline interface for interactive access to a Firebird database.It accepts DSQL statements along with a group of ISQL-specific commands to query and interact with the Firebird database.Some SET commands can be incorporated in DDL scripts to perform batch executions within isql.It also accepts DDL, DML and console commands.

The isql utility can be used in three modes:

as an interactive session;
directly from the commandline;
and as a non-interactive session, using a shell script or batch file.

Different tasks may be performed in each of the modes, as illustrated below:

An interactive session can be invoked from the commandline of the operating system shell, and lasts until the session is terminated, using a QUIT or EXIT command.Isql can be used interactively to:
- Create, update, query, and drop data or metadata
- Input a script file containing a batch of SQL statements in sequence without prompting
- Add and modify data
- Grant user permissions
- Perform database administrative functions
Directly from the commandline, with individual options and without starting an interactive session.Commands execute, and upon completion, return control automatically to the operating system.
In a non-interactive session, the user employs a shell script or batch file to perform database functions.

Note	Because other applications in the Linux environment, for example, MySQL, also use `isql` as a utility name, you are advised to run the Firebird utility from its own directory, or provide the absolute file path if you have another relational database, besides Firebird, installed on your machine.

Note

Some affected distributions have renamed Firebird’s isql to isql-fb.There may be similar changes in other distributions.

In addition, not all distributions install Firebird to the same location.OpenSuse, for example, installs just about everything to /opt/firebird/n.n but Ubuntu and derivatives install it to a number of different locations, but the utilities are in /usr/bin.

For the remainder of this document, we assume that the utility is called isql.

License Notice

The contents of this Documentation are subject to the Public Documentation License Version 1.0 (the “License”); you may only use this Documentation if you comply with the terms of this License.Copies of the License are available at https://www.firebirdsql.org/pdfmanual/pdl.pdf (PDF) and https://www.firebirdsql.org/manual/pdl.html (HTML).

The Original Documentation is titled Firebird Interactive SQL Utility.

The Initial Writer of the Original Documentation is: Kamala Vadlamani.

Contributors: Paul Vinkenoog, Norman Dunbar, Mark Rotteveel.

Invoking `Isql`

If you do not have the Firebird bin directory on your path, then either go to the bin subdirectory of your Firebird installation and type isql (Windows) or ./isql (Linux) at the command prompt, or, type the full path to the isql application to execute it.If the bin is on your path, you may start it by typing isql regardless of your operating system.

Example:

$ isql

Use CONNECT or CREATE DATABASE to specify a database
SQL> CONNECT "C:\DATABASES\FIREBIRD\MY_EMPLOYEE.FDB"
CON> user 'SYSDBA' password 'secret';

Tip	Here and elsewhere in this document, we use the ‘`$`’ to signify the command prompt, it is not part of the command to enter. For example, on Windows the command prompt might look like “`C:\>`”, or on Linux “`user@HOST:~$"`”.The exact prompt depends on the OS defaults and user configuration.

The above is the simplest method of starting isql, and once activated in this way, you must begin by either creating a new database, or connecting to one.The prompt given by isql is a hint as to what you must do next.If you wish to connect to an already existing database, you may pass the database name on the commandline.You should be aware that unless you also pass the username and password as well, you may see an error message telling you that your username or password have not been defined.In this case, you need to supply the username and password, or create two environment variables as discussed below.

The following example shows how to pass the database name plus user credentials on the commandline.

$ isql -user sysdba -password secret employee
Database:  employee, User: SYSDBA
SQL>

In this example, we used a database alias for the employee database.This example comes predefined in the file databases.conf — or aliases.conf in Firebird 2.5 and older — which normally lives in the directory that Firebird was installed in, but some Linux distributions put it in /etc/firebird/n.n where n.n is the version of the Firebird database server.There is more information on connecting to databases, using full paths or aliases in [isql-connect-database].

Commandline Switches

Commandline switches are arguments that begin with a minus/hyphen (‘-’) character.The following is an example of what happens when you attempt to start isql with the help (“-⁠?”) switch — it displays the list of valid switches with a brief explanation of each.If an invalid switch is specified, isql will also display the usage help.

$ isql -?
usage:    isql [options] [<database>]
        -a(ll)                  extract metadata incl. legacy non-SQL tables
        -b(ail)                 bail on errors (set bail on)
        -c(ache) <num>          number of cache buffers
        -ch(arset) <charset>    connection charset (set names)
        -d(atabase) <database>  database name to put in script creation
        -e(cho)                 echo commands (set echo on)
        -ex(tract)              extract metadata
        -f(etch_password)       fetch password from file
        -i(nput) <file>         input file (set input)
        -m(erge)                merge standard error
        -m2                     merge diagnostic
        -n(oautocommit)         no autocommit DDL (set autoddl off)
        -nod(btriggers)         do not run database triggers
        -now(arnings)           do not show warnings
        -o(utput) <file>        output file (set output)
        -pag(elength) <size>    page length
        -p(assword) <password>  connection password
        -q(uiet)                do not show the message "Use CONNECT..."
        -r(ole) <role>          role name
        -r2 <role>              role (uses quoted identifier)
        -s(qldialect) <dialect> SQL dialect (set sql dialect)
        -t(erminator) <term>    command terminator (set term)
        -tr(usted)              use trusted authentication
        -u(ser) <user>          user name
        -x                      extract metadata
        -z                      show program and server version

Not all of these switches appear in every release of Firebird.Some will be seen in more recent releases.Many of the switches have an equivalent set command, and these will be discussed below.

Using -⁠b(ail)

The commandline switch -⁠b(ail) instructs the isql utility to bail on error, but only when used in a non-interactive mode.

This switch prevents isql from continuing execution after an error has been detected.No further statements will be executed and isql will return an error code to the operating system.

Users will need to use the -⁠e(cho) switch to echo commands to an output file, to isolate the exact statement that caused the error.

When the server provides line and column information, users can see the exact line of the DML in the script that caused the problem.When the server only indicates failure, users can view the first line of the statement that caused the failure, in relation to the entire script.

This feature is also supported in nested scripts.For example, script A includes script B and script B causes a failure, the line number is related to script B.When script B is read completely, isql continues counting the lines related to script A, since each file gets a separate line counter.Script A includes script B when script A uses the INPUT command to load script B.

Lines are counted according to what the underlying IO layer considers separate lines.For ports using EDITLINE, a line is what readline() provides in a single call.The line length limit of 32767 bytes remains uncharged.

Using -⁠ex(tract)

The commandline switch -⁠ex(tract) can be used to extract metadata from the database.In conjunction with the -⁠o(utput) switch, it extracts the information to a specified output file.

The resultant information is the DDL to create the current structure of the database.

Using -⁠m2 and -⁠m(erge)

The commandline switch -⁠m2 — introduced in Firebird 2.0 — can be used to send the statistics and plans to the same output file that receives the input from the -⁠o(utput) switch.

Before Firebird 2.0, when a user specified that the output should be sent to a file, two options existed: the commandline switch -⁠o(utput) with a file name to store the output, or the command OUTput with a file name to store the output.Both these options could be employed either in a batch session or in the interactive isql shell.In both cases, simply passing the command OUTput would return the output to the console.While the console displayed error messages, these were not sent to the output file.

The -⁠m(erge) commandline switch, can be used to incorporate the error messages into the output files.

The -⁠m2 commandline switch ensures that the stats and plan information derived from the SET STATS, SET PER_TABLE_STATS`, SET PLAN and SET PLANONLY commands are also sent to the output file and not just returned to the console.

Note	Neither `-⁠m(erge)` nor `-⁠m2` has an interactive counterpart through a `SET` command.They are for use only as commandline `isql` options.

_Using -⁠r2 and -⁠r(ole)

These switches can be used to specify role name.The default switch for this is -⁠r(ole), and are uppercased (i.e. as unquoted identifiers, case-insensitive).With -⁠r2 they are passed to the engine exactly as typed in the commandline, that is case-sensitive (as if they are quoted identifiers).

Using `-⁠o(utput)

The OUTPUT switch allows users to store records of commands to a script file.The TMP setting on a client can be used to control where these script files will be stored, if an absolute file path is not specified.

Starting An `Isql` Session

To begin an isql session, enter the commandline options and the name of the database in the Linux /Unix shell or Windows command console.For example:

isql [options] [<database_name>]

Note	When invoking `isql`, you will need to include an appropriate `-⁠user` and `-⁠password` in your options, unless users have the `ISC_USER` and `ISC_PASSWORD` declared as operating system variables.For example: isql -user SYSDBA -password masterkey

Isql starts an interactive session if no options are specified.If no database is specified, users must connect to an existing database or create a new one after starting isql.If a database is specified, it starts the interactive session by connecting to the named database, provided the login options are accurate and valid for the specified database.Depending on the options specified, isql starts an interactive or non-interactive session.

Reading an input file and writing to an output file are not considered interactive tasks, therefore the -⁠input or -⁠output commandline options do not initiate an interactive session.Options used to extract DDL statements, such as -⁠a and -⁠x also initiate a non-interactive session.

Isql can be run from either a local or remote client:

When connecting using a local client, you may set the environment variables ISC_USER and ISC_PASSWORD.For more information on these, see below.
When connecting from a remote client, you will need a valid name and password.

Ending an `Isql` Session

There are two ways to exit isql.

If you wish to roll back all uncommitted work and exit isql type this command at the prompt:
```
SQL> QUIT;
```
If you wish to commit all your work before exiting isql, then type in the following command:
```
SQL> EXIT;
```

Getting Help

Isql comes with a basic HELP command.This gives brief details of most of the commands available — unfortunately, some are missing.The help command also allows you to drill down for further information.To activate the help system, simply type HELP at the prompt, as shown below (from Firebird 5.0):

SQL> help;
Frontend commands:
BLOBDUMP <blobid> <file>   -- dump BLOB to a file
BLOBVIEW <blobid>          -- view BLOB in text editor
EDIT     [<filename>]      -- edit SQL script file and execute
EDIT                       -- edit current command buffer and execute
HELP                       -- display this menu
INput    <filename>        -- take input from the named SQL file
OUTput   [<filename>]      -- write output to named file
OUTput                     -- return output to stdout
SET      <option>          -- (Use HELP SET for complete list)
SHELL    <command>         -- execute Operating System command in sub-shell
SHOW     <object> [<name>] -- display system information
    <object> = CHECK, COLLATION, DATABASE, DOMAIN, EXCEPTION, FILTER, FUNCTION,
               GENERATOR, GRANT, INDEX, PACKAGE, PROCEDURE, ROLE, SQL DIALECT,
               SYSTEM, TABLE, TRIGGER, VERSION, USERS, VIEW
EXIT                       -- exit and commit changes
QUIT                       -- exit and roll back changes

All commands may be abbreviated to letters in CAPitals

Most of these commands have no further level of detail, while the SET command does.To drill down into this extra level, proceed as follows:

SQL> help set;
Set commands:
    SET                    -- display current SET options
    SET AUTOddl            -- toggle autocommit of DDL statements
    SET BAIL               -- toggle bailing out on errors in non-interactive mode
    SET BLOB [ALL|<n>]     -- display BLOBS of subtype <n> or ALL
    SET BLOB               -- turn off BLOB display
    SET COUNT              -- toggle count of selected rows on/off
    SET MAXROWS [<n>]      -- limit select stmt to <n> rows, zero is no limit
    SET ECHO               -- toggle command echo on/off
    SET EXPLAIN            -- toggle display of query access plan in the explained form
    SET HEADING            -- toggle display of query column titles
    SET KEEP_TRAN_params   -- toggle to keep or not to keep text of following successful SET TRANSACTION statement
    SET LIST               -- toggle column or table display format
    SET NAMES <csname>     -- set name of runtime character set
    SET PER_TABle_stats    -- toggle display of detailed per-table statistics
    SET PLAN               -- toggle display of query access plan
    SET PLANONLY           -- toggle display of query plan without executing
    SET SQL DIALECT <n>    -- set sql dialect to <n>
    SET STATs              -- toggle display of performance statistics
    SET TIME               -- toggle display of timestamp with DATE values
    SET TERM <string>      -- change statement terminator string
    SET WIDTH <col> [<n>]  -- set/unset print width to <n> for column <col>

All commands may be abbreviated to letters in CAPitals

If you attempt to drill down into any other command, the output is the same as executing the HELP command on its own.

Note	The output from `HELP SET` only shows isql `SET` commands.Server-side `SET` statements, like `SET TRANSACTION` and management statements (e.g. `SET BIND`, `SET OPTIMIZE`, etc.), are not shown. Consult the Language Reference for your Firebird version for details on those statements.

Connecting To A Database

A sample database named employee.fdb is located in the examples/empbuild subdirectory of your Firebird installation, with an alias employee.Users can use this database to experiment with Firebird.Note that on some POSIX systems, the example database may not be located in the location given above, or may need to be installed separately.Each Linux distribution, for example, may have decided to relocate some files.

CONNECT <database_name>
  [USER username] [PASSWORD password] [ROLE role_name]

If any of the parameters to the connect command contains spaces, you must wrap that parameter in single or double quotes.Since Firebird 3.0, usernames enclosed in double quotes (‘"’) are case-sensitive, just like other delimited identifiers in Firebird.

If username or password are not supplied, then the current values in the ISC_USER and ISC_PASSWORD environment variables are used instead.There is no environment variable to preset the required role.

It is possible to connect to a database using isql in two ways: locally and remotely.

To connect locally, on Windows, use the CONNECT statement with the full file path or an alias (for a local database):
```
SQL> CONNECT "C:\DATABASES\FIREBIRD\MY_EMPLOYEE.FDB"
```
On Linux, a similar example would be:
```
SQL> CONNECT "/databases/firebird/MY_EMPLOYEE.FDB"
```
Depending on the Firebird version used, this may result in an embedded connection or an XNET connection (Windows-only).
If connecting remotely (using TCP/IP), use the CONNECT statement with the server name and complete file path of the database or, an alias. When using the full path, remember to ensure that the server name is separated from the database path with a colon.

To connect to a database on a Linux/UNIX server named cosmos:
```
SQL> CONNECT 'cosmos:/usr/firebird/examples/employee.gdb';
```
To connect to a database on a Windows server named cosmos:
```
SQL> CONNECT 'cosmos:C:\DATABASES\FIREBIRD\MY_EMPLOYEE.FDB'
```

Note	Firebird is slash agnostic and automatically converts either type of slash to suit the relevant operating system.

Connection Strings

The Firebird client library — and by extension, isql — supports a variety of connection strings.

Connection String Syntax

<database_name> ::= [server_spec]{filepath | db_alias}

<server_spec> ::=
    host[/{port | service}]:
  | \\host\
  | <protocol>://[host[:{port | service}]/]

<protocol> ::= inet | inet4 | inet6 | wnet | xnet

All Firebird versions support the first two connection strings.Firebird 3.0 and later also support the third form.Support for the wnet and xnet protocols is only available on Windows.Support for the wnet protocol was removed in Firebird 5.0.

The actual supported connection strings depends on the Firebird client library in use (fbclient.dll/libfbclient.so).

The service refers to a service definition in the services file of your operating system (Windows: %WINDIR%\System32\drivers\etc\services, Linux: /etc/services).Historically, for Firebird it is gds-db or gds_db with value 3050/tcp, however Windows and Linux do not include either entry by default.

URL-like Syntax

Firebird 3.0 introduced a unified URL-like syntax for the remote server specification.In this syntax, the first part specifies the name of the protocol, then a host name or IP address, port number, and path of the primary database file, or an alias.

The following values can be specified as the protocol:

inet: TCP/IP (first tries to connect using the IPv6 protocol, if it fails, then IPv4)
inet4: TCP/IP v4
inet6: TCP/IP v6
wnet: NetBEUI or Named Pipes Protocol (removed in Firebird 5.0)
xnet: local protocol (does not include a host, port and service name)

<protocol>://[host[:{port | service}]/]{filepath | db_alias}

The standard text form of an IPv6 address uses the colon character to separate groups of digits (upto 8 groups of digits).In the connection string, the IPv6 address must be enclosed in square brackets, to resolve the ambiguity with the use of the colon as the separator between the host IP address and database path.For example:

connect '[2014:1234::5]:test';
connect '[2014:1234::5]/3049:/srv/firebird/test.fdb';

Note	For consistency, square brackets can be optionally used around an IPv4 address or domain name.

Legacy Connection Strings

Firebird also has two “legacy” connection strings.

If you use the TCP/IP protocol to create a database, the primary file specification should look like this:

host[/{port|service}]:{filepath | db_alias}

This format is supported by all Firebird versions.

If you use the Named Pipes protocol to create a database on a Windows server, the primary file specification should look like this:

\\host\{filepath | db_alias}

This format is no longer supported since Firebird 5.0.

Using Database Aliases

In the examples above, we have been using the full path to the database file.This has the disadvantage that all clients need to know exactly where the database is to be found, or may cause problems when the database has to be moved.To alleviate these problems, database aliases can be used.

Once Firebird has been installed, a file named databases.conf (Firebird 3.0 and higher) or aliases.conf (Firebird 2.5 and earlier) can be found in the main installation folder.By adding an entry to this folder, the full path to the database can be simplified to an alias.This makes connecting easier, and allows the database to be moved around as necessary without having to change all clients to allow them to connect to the database at the new location.

To create an alias for the database currently known as /databases/firebird/MY_EMPLOYEE.FDB on the cosmos Linux server, we need to add the following to the databases.conf file on the cosmos server.By default, this will be in the folder /opt/firebird.On Linux, this file is owned by the root user and so, must be updated by the root user.On Windows, you need to be either an administrator, a power user or SYSTEM to change the file.

my_employee = /databases/firebird/MY_EMPLOYEE.FDB

There should be no quotes around the path to the database file.

Regardless of the current location of the database file, or if it has its physical filename renamed, etc., all local users can refer to the database simply as my_employee.Remote users will refer to this database as cosmos:my_employee.The following example shows an isql session connecting locally to the database using the alias rather than a full path:

$ /opt/firebird/bin/isql my_employee
Database:  test, User: sysdba

SQL>

Alternatively, a remote connection would be made as follows, specifying the server name and database alias together:

$ isql cosmos:my_employee
Database:  cosmos:my_employee

SQL>

Because the alias is defined on the server where the database resides, the remote client needs to supply the server name and alias (as defined on that server) to connect.

Using the CONNECT command in an existing isql session is equally simple using aliases:

SQL> CONNECT 'cosmos:my_employee';
Database:  cosmos:my_employee

SQL>

Caution

Do not think that aliases hide the full path to the actual database file from your users.Any user is still able to query this information from within the database:

SQL> select MON$DATABASE_NAME from mon$database;

MON$DATABASE_NAME
=================================
/data/databases/firebird/test.fdb

SQL> select RDB$GET_CONTEXT('SYSTEM', 'DB_NAME') from RDB$DATABASE;

RDB$GET_CONTEXT
=================================
/data/databases/firebird/test.fdb

Creating A Database

To create a database interactively using the isql command shell, open a command prompt in Firebird’s bin subdirectory and type isql (Windows) or ./isql (Linux):

$ isql
Use CONNECT or CREATE DATABASE to specify a database

To create a database named monkey.fdb and store it in a directory named test on your C:-drive:

SQL>CREATE DATABASE 'C:\test\monkey.fdb' page_size 8192
CON>user SYSDBA password 'masterkey';

For the full syntax of CREATE DATABASE, refer to the Language Reference of your Firebird version.For example, the Firebird 5.0 Language Reference section on CREATE DATABASE.

Note

In the CREATE DATABASE statement it is mandatory to place quote characters (single or double) around path and password.In Firebird 2.5 and earlier, it is also required to do this for usernames.Since Firebird 3.0, usernames enclosed in double quotes (‘"’) are case-sensitive, just like other delimited identifiers in Firebird.

When running Classic Server on Linux, or when using Firebird 3.0 or higher, if the database does not start with a host name, the database file will be created with the current user as the file owner.This may cause access denied errors for others who may want to connect at a later stage.By prepending the localhost: to the path, or xnet:// on Windows, the user running the server process (e.g. on Linux, user firebird) will create and own the file.

To test the newly created database type:

SQL>SELECT RDB$RELATION_ID FROM RDB$DATABASE;

RDB$RELATION_ID
===============
128

SQL> commit;

To get back to the command prompt type quit or exit.

Note	The above technique, as demonstrated, works, but ideally databases and metadata objects should be created and maintained using data definition scripts.

Transaction Handling

Transaction Handling

Script Handling

docnext count = 84

Isql Commands

BLOBDUMP

SHELL

SHOW

EXIT

QUIT

BLOBVIEW

EDIT

HELP

ADD

COPY

INput

OUTput

SET

Isql Set Commands

SET

SET HEADING

SET KEEP_TRAN_params

SET LIST

SET LOCAL_TIMEOUT

SET NAMES

SET PER_TABle_stats

SET PLAN

Effects of Various Plan-Related Commands

SET PLANONLY

SET SQLDA_DISPLAY

SET SQL DIALECT

SET AUTOddl

SET STATs

SET TIME

SET TERM

SET TRANSACTION

SET WARNINGS or SET WNG

SET WIDTH

SET BAIL

SET BLOBdisplay

SET COUNT

SET MAXROWS or SET ROWCOUNT

SET ECHO

SET EXEC_PATH_DISPLAY

SET EXPLAIN

Isql Show commands

SHOW CHECKs

SHOW GENerators

SHOW GRANTs

SHOW INDexes or SHOW INDICES

SHOW MAPping

SHOW PROCedures

SHOW PACKages

SHOW PUBlications

SHOW ROLEs

SHOW SECCLAsses

SHOW SECURITY CLAsses

SHOW COLLATIONs or SHOW COLLATEs

SHOW SEQuences

SHOW SQL DIALECT

SHOW SYStem

SHOW SCHEmas

SHOW TABLEs

SHOW TRIGgers

SHOW VERsion

SHOW USERS

SHOW VIEWs

SHOW COMMENTs

SHOW DATABASE or SHOW DB

SHOW DEPENdencies or SHOW DEPENdency

SHOW DOMAINs

SHOW EXCEPtions

SHOW FILTERs

SHOW FUNCtions

Document History

Overview

License Notice

Invoking Isql

Commandline Switches

Starting An Isql Session

`Isql` Commands

`BLOBDUMP`

`SHELL`

`SHOW`

`EXIT`

`QUIT`

`BLOBVIEW`

`EDIT`

`HELP`

`ADD`

`COPY`

`INput`

`OUTput`

`SET`

`Isql` Set Commands

`SET`

`SET HEADING`

`SET KEEP_TRAN_params`

`SET LIST`

`SET LOCAL_TIMEOUT`

`SET NAMES`

`SET PER_TABle_stats`

`SET PLAN`

`SET PLANONLY`

`SET SQLDA_DISPLAY`

`SET SQL DIALECT`

`SET AUTOddl`

`SET STATs`

`SET TIME`

`SET TERM`

`SET TRANSACTION`

`SET WARNINGS` or `SET WNG`

`SET WIDTH`

`SET BAIL`

`SET BLOBdisplay`

`SET COUNT`

`SET MAXROWS` or `SET ROWCOUNT`

`SET ECHO`

`SET EXEC_PATH_DISPLAY`

`SET EXPLAIN`

`Isql` Show commands

`SHOW CHECKs`

`SHOW GENerators`

`SHOW GRANTs`

`SHOW INDexes` or `SHOW INDICES`

`SHOW MAPping`

`SHOW PROCedures`

`SHOW PACKages`

`SHOW PUBlications`

`SHOW ROLEs`

`SHOW SECCLAsses`

`SHOW SECURITY CLAsses`

`SHOW COLLATIONs` or `SHOW COLLATEs`

`SHOW SEQuences`

`SHOW SQL DIALECT`

`SHOW SYStem`

`SHOW SCHEmas`

`SHOW TABLEs`

`SHOW TRIGgers`

`SHOW VERsion`

`SHOW USERS`

`SHOW VIEWs`

`SHOW COMMENTs`

`SHOW DATABASE` or `SHOW DB`

`SHOW DEPENdencies` or `SHOW DEPENdency`

`SHOW DOMAINs`

`SHOW EXCEPtions`

`SHOW FILTERs`

`SHOW FUNCtions`

Invoking `Isql`

Starting An `Isql` Session

Ending an `Isql` Session