The ‘sequence’ functions allows a simple and secure multi-user technique for extracting sequence values from sequence objects. Sequences are based on bigint The generator will be owned by the user issuing the command. are all distinct, not that they are generated purely Create Sequence In PostgreSQL, CREATE SEQUENCE statement creates a new sequence number generator. If specified, the sequence object is created only for this session, and is automatically dropped on session exit. Sequence is an object which returns ever-increasing numbers, different for each call, regardless of transactions etc. command: Update the sequence value after a COPY The minimum value is 1 (only one sequence numbers are to be preallocated and stored in Another consideration is that a setval executed on such a sequence will not be The specified table must have the same owner and be in the same schema as the sequence. Unexpected results might be obtained if a cache setting greater than one is used for a sequence object that will be used concurrently by multiple sessions. (Of course, this value might be obsolete by the time it's printed, if other sessions are actively doing nextval calls.). The CYCLE option allows the I've been playing with Postgres for a week or so and I'm seeing if it's possible to set the min/max values for a sequence using an expression. Unexpected results may be obtained if a cache setting greater than one is used for After a sequence is created, you use the functions The optional clause START WITH start allows the sequence to begin anywhere. By simply setting our id column as SERIAL with PRIMARY KEY attached, Postgres will handle all the complicated behind-the-scenes work and automatically increment our id column with a unique, primary key value for every INSERT.. exists, unless they are referenced with schema-qualified 13. arithmetic, so the range cannot exceed the range of an eight-byte a sequence object that will be used concurrently by multiple Sequences are created with the CREATE SEQUENCE SQL command. create a new value. this session, and is automatically dropped on session exit. following exceptions: The standard's AS