Creating Generators (Embedded SQL Guide)
Go Up to Creating Metadata
A generator is a monotonically increasing or decreasing numeric value that is inserted in a field either directly by a SQL statement in an application or through a trigger. Generators are often used to produce unique values to insert into a column used as a primary key.
To create a generator to use in an application, use the following
CREATE GENERATOR syntax:
EXEC SQL CREATE GENERATOR name;
The following statement creates a generator,
EMP_NO_GEN, to specify a unique employee number:
EXEC SQL CREATE GENERATOR EMP_NO_GEN; EXEC SQL COMMIT;
Once a generator is created, the starting value for a generated number can be specified with
SET GENERATOR. To insert a generated number in a field, use the InterBase library
GEN_ID() function in an assignment statement. For more information about
CREATE GENERATOR, and
SET GENERATOR, see the Data Definition Guide.