- Patch by Matt and chx: improved performance of taxonomy queries. When many

  terms are matched, the query would become very slow.

database/database.mysql

@@ -653,7 +653,8 @@ CREATE TABLE term_node (
   nid int(10) unsigned NOT NULL default '0',
   tid int(10) unsigned NOT NULL default '0',
   KEY nid (nid),
-  KEY tid (tid)
+  KEY tid (tid),
+  PRIMARY KEY (tid,nid)
 ) TYPE=MyISAM;
 
 --

database/database.pgsql

@@ -649,7 +649,8 @@ CREATE INDEX term_hierarchy_parent_idx ON term_hierarchy(parent);
 
 CREATE TABLE term_node (
   nid integer NOT NULL default '0',
-  tid integer NOT NULL default '0'
+  tid integer NOT NULL default '0',
+  PRIMARY KEY (tid,nid)
 );
 CREATE INDEX term_node_nid_idx ON term_node(nid);
 CREATE INDEX term_node_tid_idx ON term_node(tid);

database/updates.inc

@@ -103,7 +103,8 @@
   "2005-02-11" => "update_124",
   "2005-02-23" => "update_125",
   "2005-03-03" => "update_126",
-  "2005-03-18" => "update_127"
+  "2005-03-18" => "update_127",
+  "2005-03-21" => "update_128"
 );
 
 function update_32() {
@@ -2336,4 +2337,17 @@ function update_sql($sql) {
   }
 }
 
+function update_128() {
+  $ret = array();
+
+  if ($GLOBALS['db_type'] == 'mysql') {
+    $ret[] = update_sql('ALTER TABLE {term_node} ADD PRIMARY KEY (tid,nid)');
+  }
+  elseif ($GLOBALS['db_type'] == 'pgsql') {
+    $ret[] = update_sql('ALTER TABLE {term_node} ADD PRIMARY KEY (tid,nid)');
+  }
+
+  return $ret;
+}
+
 ?>