Re: [PATCHES] PL/Perl document patch
David Fetter wrote: > Please find enclosed a patch to the pl/perl documents that clafies > the scope of global data and gives an example of storing a code > reference. Patch installed. -- Peter Eisentraut http://developer.postgresql.org/~petere/ ---(end of broadcast)--- TIP 4: Don't 'kill -9' the postmaster
[PATCHES] PL/Perl document patch
Folks,
Please find enclosed a patch to the pl/perl documents that clafies the
scope of global data and gives an example of storing a code reference.
Cheers,
D
--
David Fetter [EMAIL PROTECTED] http://fetter.org/
phone: +1 510 893 6100 mobile: +1 415 235 3778
Remember to vote!
Index: doc/src/sgml/plperl.sgml
===
RCS file: /projects/cvsroot/pgsql/doc/src/sgml/plperl.sgml,v
retrieving revision 2.32
diff -c -r2.32 plperl.sgml
*** doc/src/sgml/plperl.sgml21 Nov 2004 21:17:01 - 2.32
--- doc/src/sgml/plperl.sgml9 Dec 2004 20:45:54 -
***
*** 315,322
Global Values in PL/Perl
!You can use the global hash %_SHARED to store
!data between function calls. For example:
CREATE OR REPLACE FUNCTION set_var(name text, val text) RETURNS text AS $$
if ($_SHARED{$_[0]} = $_[1]) {
--- 315,328
Global Values in PL/Perl
! You can use the global hash %_SHARED to store
! data, including code references, between function calls for the
! lifetime of the current session, which is bounded from below by
! the lifetime of the current transaction.
!
!
! Here is a simple example for shared data:
!
CREATE OR REPLACE FUNCTION set_var(name text, val text) RETURNS text AS $$
if ($_SHARED{$_[0]} = $_[1]) {
***
*** 333,338
--- 339,368
SELECT set_var('sample', 'Hello, PL/Perl! How's tricks?');
SELECT get_var('sample');
+Here is a slightly more complicated example using a code reference:
+
+ CREATE OR REPLACE FUNCTION myfuncs() RETURNS VOID LANGUAGE plperl AS $$
+ $_SHARED{myquote} = sub
+ {
+ my $arg = shift;
+ $arg =~ s/(['\\])/\\$1/g;
+ return "'$arg'";
+ };
+ $$;
+
+ SELECT myfuncts(); /* Initializes the function */
+
+ /* Set up a function that uses the quote function */
+
+ CREATE OR REPLACE FUNCTION use_quote(TEXT) RETURNS TEXT LANGUAGE plperl AS $$
+ my $text_to_quote = shift;
+ my $qfunc = $_SHARED{myquote};
+ return &$qfunc($text_to_quote);
+ # You could have replaced the above with the one-liner
+ # return $_SHARED{myquote}->($_[0]);
+ # at the expense of readability, but please don't code that way.
+ $$;
+
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Re: [PATCHES] PL/Perl document patch
Patch applied. Thanks. --- David Fetter wrote: > Kind people, > > The enclose patch clarifies and makes a more useful example for the > Global Values in PL/Perl section of the documents. > > Cheers, > D > -- > David Fetter [EMAIL PROTECTED] http://fetter.org/ > phone: +1 510 893 6100 mobile: +1 415 235 3778 > > Remember to vote! [ Attachment, skipping... ] > > ---(end of broadcast)--- > TIP 9: the planner will ignore your desire to choose an index scan if your > joining column's datatypes do not match -- Bruce Momjian| http://candle.pha.pa.us [EMAIL PROTECTED] | (610) 359-1001 + If your life is a hard drive, | 13 Roberts Road + Christ can be your backup.| Newtown Square, Pennsylvania 19073 ---(end of broadcast)--- TIP 4: Don't 'kill -9' the postmaster
[PATCHES] PL/Perl document patch
Kind people,
The enclose patch clarifies and makes a more useful example for the
Global Values in PL/Perl section of the documents.
Cheers,
D
--
David Fetter [EMAIL PROTECTED] http://fetter.org/
phone: +1 510 893 6100 mobile: +1 415 235 3778
Remember to vote!
? plperl.diff
Index: plperl.sgml
===
RCS file: /projects/cvsroot/pgsql-server/doc/src/sgml/plperl.sgml,v
retrieving revision 2.26
diff -u -r2.26 plperl.sgml
--- plperl.sgml 21 Jul 2004 20:44:52 - 2.26
+++ plperl.sgml 13 Aug 2004 21:42:22 -
@@ -317,23 +317,25 @@
Global Values in PL/Perl
- You can use the %_SHARED to store data between function calls. WHY
-IS THIS A HASH, AND NOT A HASH REF?
+ You can use the %_SHARED to store data between function calls.
For example:
-CREATE OR REPLACE FUNCTION set_var(TEXT) RETURNS TEXT AS $$
-$_SHARED{first} = 'Hello, PL/Perl!';
-return 'ok';
+CREATE OR REPLACE FUNCTION set_var(name TEXT, val TEXT) RETURNS TEXT AS $$
+if ($_SHARED{$_[0]} = $_[1]) {
+return 'ok';
+} else {
+return "Can't set shared variable $_[0] to $_[1]";
+}
$$ LANGUAGE plperl;
-CREATE OR REPLACE FUNCTION get_var() RETURNS text AS $$
-return $_SHARED{first};
+CREATE OR REPLACE FUNCTION get_var(name TEXT) RETURNS text AS $$
+return $_SHARED{$_[0]};
$$ LANGUAGE plperl;
-SELECT set_var('hello plperl');
-SELECT get_var();
+SELECT set_var('sample', $q$Hello, PL/Perl! How's tricks?$q$);
+SELECT get_var('sample');
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