patch #2932113 Slow export when having lots of databases

ChangeLog

@@ -6,6 +6,8 @@ $Id$
 $HeadURL: https://phpmyadmin.svn.sourceforge.net/svnroot/phpmyadmin/trunk/phpMyAdmin/ChangeLog $
 
 3.3.5.0 (not yet released)
+- patch #2932113 [information_schema] Slow export when having lots of
+  databases, thanks to Stéphane Pontier - shadow_walker
 
 3.3.4.0 (not yet released)
 - bug #2996161 [import] properly escape import value

libraries/mysql_charsets.lib.php

@@ -164,7 +164,17 @@ function PMA_getDbCollation($db) {
         return 'utf8_general_ci';
     }
 
+    if (! $GLOBALS['cfg']['Server']['DisableIS']) {
+        // this is slow with thousands of databases
         return PMA_DBI_fetch_value('SELECT DEFAULT_COLLATION_NAME FROM information_schema.SCHEMATA WHERE SCHEMA_NAME = \'' . PMA_sqlAddSlashes($db) . '\' LIMIT 1;');
+    } else {
+        PMA_DBI_select_db($db);
+        $return = PMA_DBI_fetch_value('SHOW VARIABLES LIKE \'collation_database\'', 0, 1);
+        if ($db !== $GLOBALS['db']) {
+            PMA_DBI_select_db($GLOBALS['db']);
+        }
+        return $return;
+    }
 }
 
 /**