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diff --git a/doc/man/fetch.l b/doc/man/fetch.l new file mode 100644 index 00000000000..c5a867ac45e --- /dev/null +++ b/doc/man/fetch.l @@ -0,0 +1,70 @@ +.\" This is -*-nroff-*- +.\" XXX standard disclaimer belongs here.... +.\" $Header: /cvsroot/pgsql/doc/man/Attic/fetch.l,v 1.1.1.1 1996/08/18 22:14:24 scrappy Exp $ +.TH FETCH SQL 01/23/93 Postgres95 Postgres95 +.SH NAME +fetch \(em fetch instance(s) from a cursor +.SH SYNOPSIS +.nf +\fBfetch\fR [ (\fBforward\fR | \fBbackward\fR) ] [ ( number | \fBall\fR) ] [\fBin\fR cursor_name] +.fi +.SH DESCRIPTION +.BR Fetch +allows a user to retrieve instances from a cursor named +.IR cursor_name. +The number of instances retrieved is specified by +.IR number . +If the number of instances remaining in the cursor is less than +.IR number , +then only those available are fetched. Substituting the keyword +.IR all +in place of a number will cause all remaining instances in the cursor +to be retrieved. Instances may be fetched in both +.IR forward +and +.IR backward +directions. The default direction is +.IR forward . +.PP +Updating data in a cursor is not supported by Postgres, because mapping +cursor updates back to base classes is impossible in general as with +view updates. Consequently, users must issue explicit replace +commands to update data. +.PP +Portals may only be used inside of transaction blocks marked by +.IR begin (l) +and +.IR end (l) +because the data that they store spans multiple user queries. +.SH EXAMPLE +.nf +-- +--set up and use a cursor +-- +begin + declare myportal cursor for + select * from pg-user +end +.fi +.nf +-- +--Fetch all the instances available in the portal FOO +-- +fetch all in FOO +.fi +.nf +-- +--Fetch 5 instances backward in the portal FOO +-- +fetch backward 5 in FOO +.fi +.SH "SEE ALSO" +begin(l), +end(l), +close(l), +move(l), +select(l). +.SH BUGS +Currently, the smallest transaction in Postgres is a single SQL +command. It should be possible for a single fetch to be a +transaction. |