RDB$BACKUP_HISTORY

Reserved Words and KeywordsMonitoring Tables

`RDB$BACKUP_HISTORY`

RDB$BACKUP_HISTORY stores the history of backups performed using the nBackup utility.

Column Name Data Type Description

Column Name	Data Type	Description
`RDB$BACKUP_ID`	`INTEGER`	The identifier assigned by the engine
`RDB$TIMESTAMP`	`TIMESTAMP WITH TIME ZONE`	Backup date and time
`RDB$BACKUP_LEVEL`	`INTEGER`	Backup level
`RDB$GUID`	`CHAR(38)`	Unique identifier
`RDB$SCN`	`INTEGER`	System (scan) number
`RDB$FILE_NAME`	`VARCHAR(255)`	Full path and file name of backup file

RDB$BACKUP_ID

INTEGER

The identifier assigned by the engine

RDB$TIMESTAMP

TIMESTAMP WITH TIME ZONE

Backup date and time

RDB$BACKUP_LEVEL

INTEGER

Backup level

RDB$GUID

CHAR(38)

Unique identifier

RDB$SCN

INTEGER

System (scan) number

RDB$FILE_NAME

VARCHAR(255)

Full path and file name of backup file

`RDB$INDICES`

RDB$INDICES stores definitions of both system- and user-defined indexes.The attributes of each column belonging to an index are stored in one row of the table RDB$INDEX_SEGMENTS.

Column Name Data Type Description

Column Name	Data Type	Description
`RDB$INDEX_NAME`	`CHAR(63)`	The unique name of the index specified by the user or automatically generated by the system
`RDB$RELATION_NAME`	`CHAR(63)`	The name of the table to which the index belongs.It corresponds to an identifier in `RDB$RELATION_NAME.RDB$RELATIONS`
`RDB$INDEX_ID`	`SMALLINT`	The internal (system) identifier of the index
`RDB$UNIQUE_FLAG`	`SMALLINT`	Specifies whether the index is unique: `0` - not unique `1` - unique
`RDB$DESCRIPTION`	`BLOB TEXT`	Could store comments concerning the index
`RDB$SEGMENT_COUNT`	`SMALLINT`	The number of segments (columns) in the index
`RDB$INDEX_INACTIVE`	`SMALLINT`	Indicates whether the index is currently active: `0` - active `1` - inactive
`RDB$INDEX_TYPE`	`SMALLINT`	Distinguishes between an ascending (`0` or `NULL`) and descending index (`1`).Not used in databases created before Firebird 2.0;hence, indexes in upgraded databases are more likely to store `NULL` in this column
`RDB$FOREIGN_KEY`	`CHAR(63)`	The name of the primary or unique key index referenced by the foreign key backed by this index;`NULL` if this index is not used by a foreign key.
`RDB$SYSTEM_FLAG`	`SMALLINT`	Indicates whether the index is system-defined or user-defined: `0` - user-defined `1` or greater - system-defined
`RDB$EXPRESSION_BLR`	`BLOB BLR`	The binary language representation (BLR) of the expression of an expression index, used for calculating the values for the index at runtime.
`RDB$EXPRESSION_SOURCE`	`BLOB TEXT`	The source code of the expression of an expression index
`RDB$STATISTICS`	`DOUBLE PRECISION`	Stores the last known selectivity of the entire index, calculated by execution of a `SET STATISTICS` statement over the index.It is also recalculated whenever the database is first opened by the server.The selectivity of each separate segment of the index is stored in `RDB$INDEX_SEGMENTS`.
`RDB$CONDITION_BLR`	`BLOB BLR`	The binary language representation (BLR) of the `WHERE` condition of a partial index, used for filtering the values for the index at runtime, and optimizer decisions to use the index.
`RDB$CONDITION_SOURCE`	`BLOB TEXT`	The source code of the `WHERE` condition of a partial index

RDB$INDEX_NAME

CHAR(63)

The unique name of the index specified by the user or automatically generated by the system

RDB$RELATION_NAME

CHAR(63)

The name of the table to which the index belongs.It corresponds to an identifier in RDB$RELATION_NAME.RDB$RELATIONS

RDB$INDEX_ID

SMALLINT

The internal (system) identifier of the index

RDB$UNIQUE_FLAG

SMALLINT

Specifies whether the index is unique:

0 - not unique
1 - unique

RDB$DESCRIPTION

BLOB TEXT

Could store comments concerning the index

RDB$SEGMENT_COUNT

SMALLINT

The number of segments (columns) in the index

RDB$INDEX_INACTIVE

SMALLINT

Indicates whether the index is currently active:

0 - active
1 - inactive

RDB$INDEX_TYPE

SMALLINT

Distinguishes between an ascending (0 or NULL) and descending index (1).Not used in databases created before Firebird 2.0;hence, indexes in upgraded databases are more likely to store NULL in this column

RDB$FOREIGN_KEY

CHAR(63)

The name of the primary or unique key index referenced by the foreign key backed by this index;NULL if this index is not used by a foreign key.

RDB$SYSTEM_FLAG

SMALLINT

Indicates whether the index is system-defined or user-defined:

0 - user-defined
1 or greater - system-defined

RDB$EXPRESSION_BLR

BLOB BLR

The binary language representation (BLR) of the expression of an expression index, used for calculating the values for the index at runtime.

RDB$EXPRESSION_SOURCE

BLOB TEXT

The source code of the expression of an expression index

RDB$STATISTICS

DOUBLE PRECISION

Stores the last known selectivity of the entire index, calculated by execution of a SET STATISTICS statement over the index.It is also recalculated whenever the database is first opened by the server.The selectivity of each separate segment of the index is stored in RDB$INDEX_SEGMENTS.

RDB$CONDITION_BLR

BLOB BLR

The binary language representation (BLR) of the WHERE condition of a partial index, used for filtering the values for the index at runtime, and optimizer decisions to use the index.

RDB$CONDITION_SOURCE

BLOB TEXT

The source code of the WHERE condition of a partial index