From 743766fbb34ff04df6aaeee594cf921b7ef5d7cc Mon Sep 17 00:00:00 2001
From: Greg Sabino Mullane <greg@users.mediawiki.org>
Date: Mon, 20 Apr 2009 22:43:42 +0000
Subject: [PATCH] Add $wgExtPGAlteredFields

---
 RELEASE-NOTES            |  3 +++
 maintenance/updaters.inc | 25 +++++++++++++++++++++++--
 2 files changed, 26 insertions(+), 2 deletions(-)

diff --git a/RELEASE-NOTES b/RELEASE-NOTES
index cbaae3af64..849d2b38d2 100644
--- a/RELEASE-NOTES
+++ b/RELEASE-NOTES
@@ -169,6 +169,9 @@ it from source control: http://www.mediawiki.org/wiki/Download_from_SVN
   {{REVISIONTIMESTAMP}}  (and friends) and {{REVISIONUSER}} magic words
 * (bug 18529) New hook: SoftwareInfo for adding information about the software
   to Special:Version
+* Added $wgExtPGAlteredFields to allow extensions to easily alter the data 
+  type of columns when using the Postgres backend.
+
 
 === Bug fixes in 1.15 ===
 * (bug 16968) Special:Upload no longer throws useless warnings.
diff --git a/maintenance/updaters.inc b/maintenance/updaters.inc
index ddf7ca7821..1e72ffb149 100644
--- a/maintenance/updaters.inc
+++ b/maintenance/updaters.inc
@@ -176,7 +176,8 @@ $wgUpdates = array(
 # $wgDBtype should be checked to specifiy the proper file
 $wgExtNewTables = array(); // table, dir
 $wgExtNewFields = array(); // table, column, dir
-$wgExtPGNewFields = array(); // table, column attributes; for PostgreSQL
+$wgExtPGNewFields = array(); // table, column, column attributes; for PostgreSQL
+$wgExtPGAlteredFields = array(); // table, column, new type, conversion method; for PostgreSQL
 $wgExtNewIndexes = array(); // table, index, dir
 
 # Helper function: check if the given key is present in the updatelog table.
@@ -1807,7 +1808,7 @@ function do_postgres_updates() {
 		dbsource(archive('patch-ipb_address_unique.sql'));
 	}
 
-	global $wgExtNewTables, $wgExtPGNewFields, $wgExtNewIndexes;
+	global $wgExtNewTables, $wgExtPGNewFields, $wgExtPGAlteredFields, $wgExtNewIndexes;
 	# Add missing extension tables
 	foreach ( $wgExtNewTables as $nt ) {
 		if ($wgDatabase->tableExists($nt[0])) {
@@ -1827,6 +1828,26 @@ function do_postgres_updates() {
 		wfOut( "Adding column \"$nc[0].$nc[1]\"\n" );
 		$wgDatabase->query( "ALTER TABLE $nc[0] ADD $nc[1] $nc[2]" );
 	}
+	# Change altered columns
+	foreach ( $wgExtPGAlteredFields as $nc ) {
+		$fi = $wgDatabase->fieldInfo($nc[0], $nc[1]);
+		if (is_null($fi)) {
+			wfOut( "WARNING! Column \"$nc[0].$nc[1]\" does not exist but had an alter request! Please report this.\n" );
+			continue;
+		}
+		$oldtype = $fi->type();
+		$newtype = strtolower( $nc[2] );
+		if ($oldtype === $newtype) {
+			wfOut( "... column \"$nc[0].$nc[1]\" has correct type of \"$newtype\"\n" );
+			continue;
+		}
+		$command = "ALTER TABLE $nc[0] ALTER $nc[1] TYPE $nc[2]";
+		if ( isset( $nc[3] ) ) {
+			$command .= " USING $nc[3]";
+		}
+		wfOut( "Altering column \"$nc[0].$nc[1]\" from type \"$oldtype\" to \"$newtype\"\n" );
+		$wgDatabase->query( $command );
+	}
 	# Add missing extension indexes
 	foreach ( $wgExtNewIndexes as $ni ) {
 		if (pg_index_exists($ni[0], $ni[1])) {
-- 
2.20.1