insert_record() - major efficiency improvements for Postgres databases on insert. Also fixed many calls to insert_record() which discard the returned record id to not ask for the record id.

enrol/paypal/ipn.php

@@ -184,7 +184,7 @@
 
 
         } else if (strcmp ($result, "INVALID") == 0) { // ERROR
-            insert_record("enrol_paypal", $data);
+            insert_record("enrol_paypal", $data, false);
             email_paypal_error_to_admin("Received an invalid payment notification!! (Fake payment?)", $data);
         }
     }

filter/algebra/filter.php

@@ -220,7 +220,7 @@ function algebra_filter ($courseid, $text) {
 	     $texcache->md5key = $md5;
 	     $texcache->rawtext = addslashes($texexp);
 	     $texcache->timemodified = time();
-	     insert_record("cache_filters",$texcache);
+	     insert_record("cache_filters",$texcache, false);
              $text = str_replace( $matches[0][$i], string_file_picture_algebra($filename, $texexp), $text);
 	   } else {
 	     $text = str_replace( $matches[0][$i],"<b>Undetermined error:</b> ",$text);

filter/tex/filter.php

@@ -132,7 +132,7 @@ function tex_filter ($courseid, $text) {
             $texcache->md5key = $md5;
             $texcache->rawtext = addslashes($texexp);
             $texcache->timemodified = time();
-            insert_record("cache_filters",$texcache);
+            insert_record("cache_filters",$texcache, false);
         }
         $filename = $md5 . ".gif";
         $text = str_replace( $matches[0][$i], string_file_picture_tex($filename, $texexp), $text);

lib/datalib.php

@@ -907,6 +907,19 @@ function insert_record($table, $dataobject, $returnid=true, $primarykey='id') {
         return false;
     }
 
+    /// Postgres doesn't have the concept of primary key built in
+    /// and will return the OID which isn't what we want.
+    /// The efficient and transaction-safe strategy is to 
+    /// move the sequence forward first, and make the insert
+    /// with an explicit id.
+    if ( !isset($dataobject->{$primarykey}) 
+         && $CFG->dbtype === 'postgres7'      
+         && $returnid == true ) {        
+        if ($nextval = get_field_sql("SELECT NEXTVAL('{$CFG->prefix}{$table}_{$primarykey}_seq')")) {
+            $dataobject->{$primarykey} = $nextval;            
+        } 
+    }
+
 /// Get the correct SQL from adoDB
     if (!$insertSQL = $db->GetInsertSQL($rs, (array)$dataobject, true)) {
         return false;
@@ -925,20 +938,32 @@ function insert_record($table, $dataobject, $returnid=true, $primarykey='id') {
         return true;
     }
 
-/// Find the return ID of the newly inserted record
-    switch ($CFG->dbtype) {
-        case "postgres7":             // Just loves to be special
-            $oid = $db->Insert_ID();
-            if ($rs = $db->Execute("SELECT $primarykey FROM $CFG->prefix$table WHERE oid = $oid")) {
-                if ($rs->RecordCount() == 1) {
-                    return (integer) $rs->fields[0];
-                }
-            }
-            return false;
-
-        default:
-            return $db->Insert_ID();  // Should work on most databases, but not all!
+/// We already know the record PK
+/// if it's been passed explicitly,
+/// or if we've retrieved it from a 
+/// sequence (Postgres).
+    if (isset($dataobject->{$primarykey})) {
+        return $dataobject->{$primarykey};
     }
+
+/// This only gets triggered with non-Postgres databases
+/// however we have some postgres fallback in case we failed 
+/// to find the sequence.
+    $id = $db->Insert_ID();  
+
+    if ($CFG->dbtype === 'postgres7') {
+        // try to get the primary key based on id
+        if ( ($rs = $db->Execute('SELECT '. $primarykey .' FROM '. $CFG->prefix . $table .' WHERE oid = '. $id))
+             && ($rs->RecordCount() == 1) ) {
+            trigger_error("Retrieved $primarykey from oid on table $table because we could not find the sequence.");
+            return (integer)$rs->fields[0];
+        } 
+        trigger_error('Failed to retrieve primary key after insert: SELECT '. $primarykey .' FROM '. $CFG->prefix . $table .' WHERE oid = '. $id);
+        return false;
+    }
+
+    return (integer)$id;
+    
 }
 
 

mod/chat/chatd.php

@@ -321,7 +321,7 @@ class ChatDaemon {
                 $msg->timestamp = time();
 
                 // Commit to DB
-                insert_record('chat_messages', $msg);
+                insert_record('chat_messages', $msg, false);
 
                 // OK, now push it out to all users
                 $this->message_broadcast($msg, $this->sets_info[$sessionid]['user']);
@@ -415,7 +415,7 @@ class ChatDaemon {
                 $msg->message = addslashes($msg->message);
 
                 // Commit to DB
-                insert_record('chat_messages', $msg);
+                insert_record('chat_messages', $msg, false);
 
                 // Undo the hack
                 $msg->message = $origmsg;
@@ -537,7 +537,7 @@ class ChatDaemon {
         $msg->message = 'enter';
         $msg->timestamp = time();
 
-        insert_record('chat_messages', $msg);
+        insert_record('chat_messages', $msg, false);
         $this->message_broadcast($msg, $this->sets_info[$sessionid]['user']);
 
         return true;
@@ -740,7 +740,7 @@ class ChatDaemon {
         $msg->timestamp = time();
 
         $this->trace('User has disconnected, destroying uid '.$info['userid'].' with SID '.$sessionid, E_USER_WARNING);
-        insert_record('chat_messages', $msg);
+        insert_record('chat_messages', $msg, false);
 
         // *************************** IMPORTANT
         //

mod/glossary/edit.php

@@ -176,7 +176,7 @@ if ( $confirm ) {
         foreach ($form->categories as $category) {
             if ( $category > 0 ) {
                 $newcategory->categoryid = $category;
-                insert_record("glossary_entries_categories",$newcategory);
+                insert_record("glossary_entries_categories",$newcategory, false);
             } else {
                 break;
             }
@@ -190,7 +190,7 @@ if ( $confirm ) {
                     unset($newalias);
                     $newalias->entryid = $e;
                     $newalias->alias = $alias;
-                    insert_record("glossary_alias",$newalias);
+                    insert_record("glossary_alias",$newalias, false);
                 }
             }
         }