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CREATE SEQUENCE(7)                 PostgreSQL 14.23 Documentation                 CREATE SEQUENCE(7)



NAME
       CREATE_SEQUENCE - define a new sequence generator

SYNOPSIS
       CREATE [ TEMPORARY | TEMP ] SEQUENCE [ IF NOT EXISTS ] name
           [ AS data_type ]
           [ INCREMENT [ BY ] increment ]
           [ MINVALUE minvalue | NO MINVALUE ] [ MAXVALUE maxvalue | NO MAXVALUE ]
           [ START [ WITH ] start ] [ CACHE cache ] [ [ NO ] CYCLE ]
           [ OWNED BY { table_name.column_name | NONE } ]

DESCRIPTION
       CREATE SEQUENCE creates a new sequence number generator. This involves creating and
       initializing a new special single-row table with the name name. The generator will be owned
       by the user issuing the command.

       If a schema name is given then the sequence is created in the specified schema. Otherwise it
       is created in the current schema. Temporary sequences exist in a special schema, so a schema
       name cannot be given when creating a temporary sequence. The sequence name must be distinct
       from the name of any other sequence, table, index, view, or foreign table in the same schema.

       After a sequence is created, you use the functions nextval, currval, and setval to operate on
       the sequence. These functions are documented in Section 9.17.

       Although you cannot update a sequence directly, you can use a query like:

           SELECT * FROM name;

       to examine the parameters and current state of a sequence. In particular, the last_value
       field of the sequence shows the last value allocated by any session. (Of course, this value
       might be obsolete by the time it's printed, if other sessions are actively doing nextval
       calls.)

PARAMETERS
       TEMPORARY or TEMP
           If specified, the sequence object is created only for this session, and is automatically
           dropped on session exit. Existing permanent sequences with the same name are not visible
           (in this session) while the temporary sequence exists, unless they are referenced with
           schema-qualified names.

       IF NOT EXISTS
           Do not throw an error if a relation with the same name already exists. A notice is issued
           in this case. Note that there is no guarantee that the existing relation is anything like
           the sequence that would have been created — it might not even be a sequence.

       name
           The name (optionally schema-qualified) of the sequence to be created.

       data_type
           The optional clause AS data_type specifies the data type of the sequence. Valid types are
           smallint, integer, and bigint.  bigint is the default. The data type determines the
           default minimum and maximum values of the sequence.

       increment
           The optional clause INCREMENT BY increment specifies which value is added to the current
           sequence value to create a new value. A positive value will make an ascending sequence, a
           negative one a descending sequence. The default value is 1.

       minvalue
       NO MINVALUE
           The optional clause MINVALUE minvalue determines the minimum value a sequence can
           generate. If this clause is not supplied or NO MINVALUE is specified, then defaults will
           be used. The default for an ascending sequence is 1. The default for a descending
           sequence is the minimum value of the data type.

       maxvalue
       NO MAXVALUE
           The optional clause MAXVALUE maxvalue determines the maximum value for the sequence. If
           this clause is not supplied or NO MAXVALUE is specified, then default values will be
           used. The default for an ascending sequence is the maximum value of the data type. The
           default for a descending sequence is -1.

       start
           The optional clause START WITH start allows the sequence to begin anywhere. The default
           starting value is minvalue for ascending sequences and maxvalue for descending ones.

       cache
           The optional clause CACHE cache specifies how many sequence numbers are to be
           preallocated and stored in memory for faster access. The minimum value is 1 (only one
           value can be generated at a time, i.e., no cache), and this is also the default.

       CYCLE
       NO CYCLE
           The CYCLE option allows the sequence to wrap around when the maxvalue or minvalue has
           been reached by an ascending or descending sequence respectively. If the limit is
           reached, the next number generated will be the minvalue or maxvalue, respectively.

           If NO CYCLE is specified, any calls to nextval after the sequence has reached its maximum
           value will return an error. If neither CYCLE or NO CYCLE are specified, NO CYCLE is the
           default.

       OWNED BY table_name.column_name
       OWNED BY NONE
           The OWNED BY option causes the sequence to be associated with a specific table column,
           such that if that column (or its whole table) is dropped, the sequence will be
           automatically dropped as well. The specified table must have the same owner and be in the
           same schema as the sequence.  OWNED BY NONE, the default, specifies that there is no such
           association.

NOTES
       Use DROP SEQUENCE to remove a sequence.

       Sequences are based on bigint arithmetic, so the range cannot exceed the range of an
       eight-byte integer (-9223372036854775808 to 9223372036854775807).

       Because nextval and setval calls are never rolled back, sequence objects cannot be used if
       “gapless” assignment of sequence numbers is needed. It is possible to build gapless
       assignment by using exclusive locking of a table containing a counter; but this solution is
       much more expensive than sequence objects, especially if many transactions need sequence
       numbers concurrently.

       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. Each session will
       allocate and cache successive sequence values during one access to the sequence object and
       increase the sequence object's last_value accordingly. Then, the next cache-1 uses of nextval
       within that session simply return the preallocated values without touching the sequence
       object. So, any numbers allocated but not used within a session will be lost when that
       session ends, resulting in “holes” in the sequence.

       Furthermore, although multiple sessions are guaranteed to allocate distinct sequence values,
       the values might be generated out of sequence when all the sessions are considered. For
       example, with a cache setting of 10, session A might reserve values 1..10 and return
       nextval=1, then session B might reserve values 11..20 and return nextval=11 before session A
       has generated nextval=2. Thus, with a cache setting of one it is safe to assume that nextval
       values are generated sequentially; with a cache setting greater than one you should only
       assume that the nextval values are all distinct, not that they are generated purely
       sequentially. Also, last_value will reflect the latest value reserved by any session, whether
       or not it has yet been returned by nextval.

       Another consideration is that a setval executed on such a sequence will not be noticed by
       other sessions until they have used up any preallocated values they have cached.

EXAMPLES
       Create an ascending sequence called serial, starting at 101:

           CREATE SEQUENCE serial START 101;

       Select the next number from this sequence:

           SELECT nextval('serial');

            nextval
           ---------
                101

       Select the next number from this sequence:

           SELECT nextval('serial');

            nextval
           ---------
                102

       Use this sequence in an INSERT command:

           INSERT INTO distributors VALUES (nextval('serial'), 'nothing');

       Update the sequence value after a COPY FROM:

           BEGIN;
           COPY distributors FROM 'input_file';
           SELECT setval('serial', max(id)) FROM distributors;
           END;

COMPATIBILITY
       CREATE SEQUENCE conforms to the SQL standard, with the following exceptions:

       •   Obtaining the next value is done using the nextval() function instead of the standard's
           NEXT VALUE FOR expression.

       •   The OWNED BY clause is a PostgreSQL extension.

SEE ALSO
       ALTER SEQUENCE (ALTER_SEQUENCE(7)), DROP SEQUENCE (DROP_SEQUENCE(7))



PostgreSQL 14.23                                2026                              CREATE SEQUENCE(7)