The Firebird 5.0 Language Reference | CREATE OR ALTER EXCEPTION

`CREATE OR ALTER EXCEPTION`

Creates a custom exception if it doesn’t exist, or alters a custom exception

Available in

DSQL

Syntax

CREATE OR ALTER EXCEPTION exception_name '<message>'

!! See syntax of CREATE EXCEPTION for further rules !!

The statement CREATE OR ALTER EXCEPTION is used to create the specified exception if it does not exist, or to modify the text of the error message returned from it if it exists already.If an existing exception is altered by this statement, any existing dependencies will remain intact.

`CREATE OR ALTER EXCEPTION` Example

Changing the message for the exception E_LARGE_VALUE

CREATE OR ALTER EXCEPTION E_LARGE_VALUE
  'The value is higher than the permitted range 0 to 32,765';

`DROP EXCEPTION`

Drops a custom exception

Available in

DSQL, ESQL

Syntax

DROP EXCEPTION exception_name

Table 1. `DROP EXCEPTION` Statement Parameter
Parameter	Description
exception_name	Exception name

The statement DROP EXCEPTION is used to delete an exception.Any dependencies on the exception will cause the statement to fail, and the exception will not be deleted.

Who Can Drop an Exception

The DROP EXCEPTION statement can be executed by:

Administrators
The owner of the exception
Users with the DROP ANY EXCEPTION privilege

`DROP EXCEPTION` Examples

Dropping exception E_LARGE_VALUE

DROP EXCEPTION E_LARGE_VALUE;

`RECREATE EXCEPTION`

Drops a custom exception if it exists, and creates a custom exception

Available in

DSQL

Syntax

RECREATE EXCEPTION exception_name '<message>'

!! See syntax of CREATE EXCEPTION for further rules !!

The statement RECREATE EXCEPTION creates a new exception for use in PSQL modules.If an exception with the same name exists already, the RECREATE EXCEPTION statement will try to drop it and create a new one.If there are any dependencies on the existing exception, the attempted deletion fails and RECREATE EXCEPTION is not executed.

`RECREATE EXCEPTION` Example

Recreating the E_LARGE_VALUE exception

RECREATE EXCEPTION E_LARGE_VALUE
  'The value exceeds its limit';

CREATE OR ALTER EXCEPTION

CREATE OR ALTER EXCEPTION

CREATE OR ALTER EXCEPTION Example

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DROP EXCEPTION

Who Can Drop an Exception

DROP EXCEPTION Examples

RECREATE EXCEPTION

RECREATE EXCEPTION Example

`CREATE OR ALTER EXCEPTION`

`CREATE OR ALTER EXCEPTION` Example

`DROP EXCEPTION`

`DROP EXCEPTION` Examples

`RECREATE EXCEPTION`

`RECREATE EXCEPTION` Example