ALTER SEQUENCE
  SQL - Language Statements
 
 
  
   ALTER SEQUENCE
  
  
   change the definition of a sequence generator
  
  
 
  ALTER SEQUENCE
 
 
  
ALTER SEQUENCE name [ INCREMENT [ BY ] increment ]
    [ MINVALUE minvalue | NO MINVALUE ] [ MAXVALUE maxvalue | NO MAXVALUE ]
    [ RESTART [ WITH ] start ] [ CACHE cache ] [ [ NO ] CYCLE ]
ALTER SEQUENCE name SET SCHEMA new_schema
  
 
 
  Description
  
   ALTER SEQUENCE changes the parameters of an existing
   sequence generator.  Any parameters not specifically set in the
   ALTER SEQUENCE command retain their prior settings.
  
  
   You must own the sequence to use ALTER SEQUENCE>.
   To change a sequence's schema, you must also have CREATE>
   privilege on the new schema.
  
 
 
  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 behavior will be
        maintained.
       
      
     
     
      new_schema
      
       
        The new schema for the sequence.
       
      
     
    
   
  
 
  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.
  
  
   Some variants of ALTER TABLE can be used with
   sequences as well; for example, to rename a sequence use ALTER
   TABLE RENAME.
  
 
 
  Compatibility
  
   ALTER SEQUENCE conforms to the SQL
   standard,
   except for the SET SCHEMA variant, which is a
   PostgreSQL extension.