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ALTER
NAME
  ALTER SEQUENCE - alter the definition of a sequence generator

SYNOPSIS
  ALTER SEQUENCE name [ INCREMENT [ BY ] increment ]
      [ MINVALUE minvalue | NO MINVALUE ] [ MAXVALUE maxvalue | NO MAXVALUE ]
      [ RESTART [ WITH ] start ] [ CACHE cache ] [ [ NO ] CYCLE ]

DESCRIPTION
  ALTER SEQUENCE changes the parameters of an existing sequence generator.
  Any parameter not specifically set in the ALTER SEQUENCE command retains
  its prior setting.

PARAMETERS
  name The name (optionally schema-qualified) of a sequence to be altered.

  increment
       The clause INCREMENT BY increment is optional. A positive value will
       make an ascending sequence, a negative one a descending sequence. If
       unspecified, the old increment value will be maintained.

  minvalue

  NO MINVALUE
       The optional clause MINVALUE minvalue determines the minimum value a
       sequence can generate. If NO MINVALUE is specified, the defaults of 1
       and -263-1 for ascending and descending sequences, respectively, will
       be used. If neither option is specified, the current minimum value
       will be maintained.

  maxvalue

  NO MAXVALUE
       The optional clause MAXVALUE maxvalue determines the maximum value for
       the sequence. If NO MAXVALUE is specified, the defaults are 263-1 and
       -1 for ascending and descending sequences, respectively, will be used.
       If neither option is specified, the current maximum value will be
       maintained.

  start
       The optional clause RESTART WITH start changes the current value of
       the sequence.

  cache
       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 will be maintained.

  CYCLE
       The optional CYCLE key word may 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.

  NO CYCLE
       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 or NO CYCLE are specified, the old cycle behaviour
       will be maintained.

EXAMPLES
  Restart a sequence called serial, at 105:

  ALTER SEQUENCE serial RESTART WITH 105;

NOTES
  To avoid blocking of concurrent transactions that obtain numbers from the
  same sequence, ALTER SEQUENCE is never rolled back; the changes take effect
  immediately and are not reversible.

  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 parameters. The current backend will be affected immediately.

COMPATIBILITY
  SQL99

  ALTER SEQUENCE is a PostgreSQL language extension.  There is no ALTER
  SEQUENCE statement in SQL99.

Index for Section SEQUENCE

Alphabetical listing for A

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