Manuals for SEQUENCEs.

src/man/create_sequence.l

+.\" This is -*-nroff-*-
+.\" XXX standard disclaimer belongs here....
+.\" $Header: /cvsroot/pgsql/src/man/Attic/create_sequence.l,v 1.1 1997/04/02 04:19:58 vadim Exp $
+.TH "CREATE SEQUENCE" SQL 04/01/97 PostgreSQL PostgreSQL
+.SH NAME
+create sequence \(em create a new sequence number generator
+.SH SYNOPSIS
+.nf
+\fBcreate sequence\fR seqname 
+	[\fBincrement\fP incby_value] 
+	[\fBminvalue\fP min_value] 
+	[\fBmaxvalue\fP max_value] 
+	[\fBstart\fP start_value] 
+	[\fBcache\fP cache_value] 
+	[\fBcycle\fP] 
+.fi
+.SH DESCRIPTION
+.BR "Create sequence"
+will enter a new sequence number generator into the current data base.
+Actually, new single block
+.BR table
+with name 
+.IR seqname
+will be created and initialized. 
+The generator will be
+\*(lqowned\*(rq by the user issuing the command.
+.PP
+The 
+.BR "increment"
+is optional clause. Positive value will make ascending sequence,
+negative - descending. Default value is 1. 
+.PP
+The optional integer
+.BR minvalue
+determines the minimum value a sequence can be. Defaults are
+1/-2147483647 for ascending/descending sequences.
+.PP
+Use optional integer
+.BR maxvalue
+to determine the maximum value for sequence. Defaults are
+2147483647/-1 for ascending/descending sequences.
+.PP
+The optinal
+.BR "start"
+value enables sequence to begin anywhere.  Default is 
+.BR minvalue
+for ascending sequences and 
+.BR maxvalue
+for descending ones.
+.PP
+The
+.BR cache
+option enables sequence numbers to be preallocated and 
+stored in memory for faster access. The minimum value is 1 
+(i.e. - no cache) and it is default.
+.BR NOTE: 
+each backend uses own cache to store allocated numbers.
+Cached but not used in current session numbers will be lost.
+.PP
+The optional
+.BR cycle
+keyword may be used to enable sequence to continue when the 
+.BR maxvalue/minvalue 
+has been reached by ascending/descending sequence.
+If the limit is reached, the next number generated will be 
+whatever the 
+.BR minvalue/maxvalue 
+is.
+.PP
+After sequence created, You may use function
+.BR nextval
+with sequence name as argument to get new number from sequence
+specified.
+To determine the current sequence number use function 
+.BR currval 
+('sequence_name'). 
+.BR NOTE:
+after sequence creation You are to call 
+.BR nextval
+before first call to
+.BR currval.
+.PP
+.nf
+Use query like
+
+select * from <sequence_name>;
+
+to get parameters of a sequence.
+.fi
+.PP
+Low-level locking is used to enable multiple simultaneous calls
+to a generator.
+.PP
+.SH EXAMPLES
+.nf
+--
+-- Create sequence seq caching 2 numbers, starting with 10
+--
+create sequence seq cache 2 start 10;
+.fi
+.nf
+--
+-- Select next number from sequence
+--
+select nextval ('seq');
+.fi
+.nf
+--
+-- Use sequence in insert
+--
+insert into table _table_ values (nextval ('seq'),...);
+.fi
+.SH "SEE ALSO"
+drop sequence(l).

src/man/drop_sequence.l

+.\" This is -*-nroff-*-
+.\" XXX standard disclaimer belongs here....
+.\" $Header: /cvsroot/pgsql/src/man/Attic/drop_sequence.l,v 1.1 1997/04/02 04:20:00 vadim Exp $
+.TH "DROP TABLE" SQL 04/01/97 PostgreSQL PostgreSQL
+.SH NAME
+drop sequence \(em destroy existing sequence
+.SH SYNOPSIS
+.nf
+\fBdrop sequence\fR sequence_name_1 { \fB,\fR sequence_name_N }
+.fi
+.SH DESCRIPTION
+.BR "Drop Sequence"
+removes sequence number generators from the data base.  
+With current implementation of sequences as special tables it
+works just like \fBdrop table\fR(l).