ALTER_SEQUENCE(7pg17)

πŸ“¦ version 17.11, in opensuse-leap 16.0

✨ ALTER SEQUENCE πŸ’…

Okay bestie, so this page is about ALTER_SEQUENCE β€” it's the PostgreSQL 17.11 doc for changing the definition of a sequence generator 🌸. Think of it like giving your sequence a little glow-up: you can tweak its settings, swap its owner, rename it, move it to a new schema β€” all the main character moves ✨. Fr fr, let's get into it.


πŸ’– SYNOPSIS πŸŽ€

ALTER SEQUENCE [ IF EXISTS ] name
    [ AS data_type ]
    [ INCREMENT [ BY ] increment ]
    [ MINVALUE minvalue | NO MINVALUE ] [ MAXVALUE maxvalue | NO MAXVALUE ]
    [ START [ WITH ] start ]
    [ RESTART [ [ WITH ] restart ] ]
    [ CACHE cache ] [ [ NO ] CYCLE ]
    [ OWNED BY { table_name.column_name | NONE } ]
ALTER SEQUENCE [ IF EXISTS ] name SET { LOGGED | UNLOGGED }
ALTER SEQUENCE [ IF EXISTS ] name OWNER TO { new_owner | CURRENT_ROLE | CURRENT_USER | SESSION_USER }
ALTER SEQUENCE [ IF EXISTS ] name RENAME TO new_name
ALTER SEQUENCE [ IF EXISTS ] name SET SCHEMA new_schema

🌈 DESCRIPTION ✨

So <pink>ALTER SEQUENCE</pink> changes the parameters of an existing sequence generator, periodt πŸ’…. Any parameters you don't specifically set in the command just keep their prior settings β€” no cap, they stay exactly where they were 🫢.

Like, you literally must own the sequence to use ALTER SEQUENCE. And if you're changing a sequence's schema, you also need CREATE privilege on the new schema. To alter the owner, you have to be able to SET ROLE to the new owning role, and that role has to have CREATE privilege on the sequence's schema. (These restrictions enforce that altering the owner doesn't do anything you couldn't do by dropping and recreating the sequence. However, a superuser can alter ownership of any sequence anyway πŸ‘‘.)


πŸ¦‹ PARAMETERS πŸ’œ

  • name β€” the name (optionally schema-qualified) of a sequence to be altered. iykyk.
  • IF EXISTS β€” do not throw an error if the sequence doesn't exist. A notice is issued in this case. So chill, bestie, it won't blow up 😌.
  • data_type β€” the optional clause AS data_type changes the data type of the sequence. Valid types are smallint, integer, and bigint ✨.

Changing the data type automatically changes the minimum and maximum values of the sequence if and only if the previous minimum and maximum values were the minimum or maximum value of the old data type (in other words, if the sequence had been created using NO MINVALUE or NO MAXVALUE, implicitly or explicitly). Otherwise, the minimum and maximum values are preserved, unless new values are given as part of the same command. If the minimum and maximum values don't fit into the new data type, an error will be generated 🚨.

  • increment β€” the clause INCREMENT BY increment is optional. A positive value makes an ascending sequence, a negative one makes a descending sequence. If unspecified, the old increment value is maintained πŸŽ€.
  • minvalue, NO MINVALUE β€” the optional clause MINVALUE minvalue determines the minimum value a sequence can generate. If NO MINVALUE is specified, the defaults of 1 and the minimum value of the data type for ascending and descending sequences, respectively, will be used. If neither option is specified, the current minimum value is maintained πŸ’–.
  • maxvalue, NO MAXVALUE β€” the optional clause MAXVALUE maxvalue determines the maximum value for the sequence. If NO MAXVALUE is specified, the defaults of the maximum value of the data type and -1 for ascending and descending sequences, respectively, will be used. If neither option is specified, the current maximum value is maintained 🌸.
  • start β€” the optional clause START WITH start changes the recorded start value of the sequence. This has no effect on the current sequence value; it simply sets the value that future ALTER SEQUENCE RESTART commands will use. It's giving "set it and forget it" energy πŸ’….
  • restart β€” the optional clause RESTART [ WITH restart ] changes the current value of the sequence. This is similar to calling the setval function with is_called = false: the specified value will be returned by the next call of nextval. Writing RESTART with no restart value is equivalent to supplying the start value that was recorded by CREATE SEQUENCE or last set by ALTER SEQUENCE START WITH πŸ¦‹.

In contrast to a setval call, a RESTART operation on a sequence is transactional and blocks concurrent transactions from obtaining numbers from the same sequence. If that's not the desired mode of operation, setval should be used. Lowkey important, bestie πŸ”₯.

  • cache β€” the clause CACHE cache enables sequence numbers 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). If unspecified, the old cache value is maintained ⚑.
  • CYCLE β€” the optional CYCLE key word can be used to enable 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. It's giving circular energy πŸ”„.
  • NO CYCLE β€” if the optional NO CYCLE key word is specified, any calls to nextval after the sequence has reached its maximum value will return an error. If neither CYCLE nor NO CYCLE are specified, the old cycle behavior is maintained πŸ›‘.
  • SET { LOGGED | UNLOGGED } β€” this form changes the sequence from unlogged to logged or vice-versa (see CREATE SEQUENCE (CREATE_SEQUENCE(7))). It cannot be applied to a temporary sequence. No temporary glow-ups allowed πŸ™…β€β™€οΈ.
  • OWNED BY table_name.column_name, OWNED BY NONE β€” 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. If specified, this association replaces any previously specified association for the sequence. The specified table must have the same owner and be in the same schema as the sequence. Specifying OWNED BY NONE removes any existing association, making the sequence "free-standing" πŸ•ŠοΈ.
  • new_owner β€” the user name of the new owner of the sequence πŸ‘‘.
  • new_name β€” the new name for the sequence ✨.
  • new_schema β€” the new schema for the sequence πŸŽ€.

🌟 NOTES 🧚

ALTER SEQUENCE will not immediately affect nextval results in backends, other than the current one, that have preallocated (cached) sequence values. They will use up all cached values prior to noticing the changed sequence generation parameters. The current backend is affected immediately, tho πŸ’….

ALTER SEQUENCE does not affect the currval status for the sequence. (Before PostgreSQL 8.3, it sometimes did. Ancient history, bestie 😭.)

ALTER SEQUENCE blocks concurrent nextval, currval, lastval, and setval calls. It's a whole vibe check for concurrent access 🚦.

For historical reasons, ALTER TABLE can be used with sequences too; but the only variants of ALTER TABLE that are allowed with sequences are equivalent to the forms shown above. Nostalgic, but valid 🫢.


🌈 EXAMPLES πŸ“

Restart a sequence called serial, at 105:

ALTER SEQUENCE serial RESTART WITH 105;

Slay, that's it. Short and iconic ✨.


πŸ’« COMPATIBILITY πŸ’œ

ALTER SEQUENCE conforms to the SQL standard, except for the AS, START WITH, OWNED BY, OWNER TO, RENAME TO, and SET SCHEMA clauses, which are PostgreSQL extensions. We're extra like that πŸ’….


πŸ”₯ SEE ALSO 🌸


PostgreSQL 17.11, dated 2026 β€” that's the tea, bestie πŸŽ€βœ¨. Now go alter those sequences and live your main character era πŸ’–πŸ‘‘.

πŸ“¦ where this page comes from