From f3b22cd894980c5a93a9dc7cb08dba06e550549d Mon Sep 17 00:00:00 2001
From: Greg Sabino Mullane <greg@users.mediawiki.org>
Date: Mon, 17 Jul 2006 00:54:40 +0000
Subject: [PATCH] Add mCascadingDeletes and mCleanupTriggers properties to
 Database*, use accessor methods to determine what to delete in Article.php

---
 includes/Article.php          | 36 ++++++++++++++++++++---------------
 includes/Database.php         | 16 ++++++++++++++++
 includes/DatabasePostgres.php |  3 ++-
 3 files changed, 39 insertions(+), 16 deletions(-)

diff --git a/includes/Article.php b/includes/Article.php
index 64168896a0..f5d1de60d9 100644
--- a/includes/Article.php
+++ b/includes/Article.php
@@ -1910,29 +1910,35 @@ class Article {
 		);
 
 		# Now that it's safely backed up, delete it
-		$dbw->delete( 'revision', array( 'rev_page' => $id ), __METHOD__ );
 		$dbw->delete( 'page', array( 'page_id' => $id ), __METHOD__);
 
-		if ($wgUseTrackbacks)
-			$dbw->delete( 'trackbacks', array( 'tb_page' => $id ), __METHOD__ );
+		# If using cascading deletes, we can skip some explicit deletes
+		if ( !$dbw->cascadingDeletes() ) {
+
+			$dbw->delete( 'revision', array( 'rev_page' => $id ), __METHOD__ );
 
- 		# Clean up recentchanges entries...
-		$dbw->delete( 'recentchanges', array( 'rc_namespace' => $ns, 'rc_title' => $t ), __METHOD__ );
+			if ($wgUseTrackbacks)
+				$dbw->delete( 'trackbacks', array( 'tb_page' => $id ), __METHOD__ );
+
+			# Delete outgoing links
+			$dbw->delete( 'pagelinks', array( 'pl_from' => $id ) );
+			$dbw->delete( 'imagelinks', array( 'il_from' => $id ) );
+			$dbw->delete( 'categorylinks', array( 'cl_from' => $id ) );
+			$dbw->delete( 'templatelinks', array( 'tl_from' => $id ) );
+			$dbw->delete( 'externallinks', array( 'el_from' => $id ) );
+			$dbw->delete( 'langlinks', array( 'll_from' => $id ) );
+		}
 
-		# Finally, clean up the link tables
-		$t = $this->mTitle->getPrefixedDBkey();
+		# If using cleanup triggers, we can skip some manual deletes
+		if ( !$dbw->cleanupTriggers() ) {
+
+			# Clean up recentchanges entries...
+			$dbw->delete( 'recentchanges', array( 'rc_namespace' => $ns, 'rc_title' => $t ), __METHOD__ );
+		}
 
 		# Clear caches
 		Article::onArticleDelete( $this->mTitle );
 
-		# Delete outgoing links
-		$dbw->delete( 'pagelinks', array( 'pl_from' => $id ) );
-		$dbw->delete( 'imagelinks', array( 'il_from' => $id ) );
-		$dbw->delete( 'categorylinks', array( 'cl_from' => $id ) );
-		$dbw->delete( 'templatelinks', array( 'tl_from' => $id ) );
-		$dbw->delete( 'externallinks', array( 'el_from' => $id ) );
-		$dbw->delete( 'langlinks', array( 'll_from' => $id ) );
-
 		# Log the deletion
 		$log = new LogPage( 'delete' );
 		$log->addEntry( 'delete', $this->mTitle, $reason );
diff --git a/includes/Database.php b/includes/Database.php
index 79de31346a..7ffa294587 100644
--- a/includes/Database.php
+++ b/includes/Database.php
@@ -244,6 +244,8 @@ class Database {
 	protected $mTrxLevel = 0;
 	protected $mErrorCount = 0;
 	protected $mLBInfo = array();
+	protected $mCascadingDeletes = false;
+	protected $mCleanupTriggers = false;
 
 #------------------------------------------------------------------------------
 # Accessors
@@ -334,6 +336,20 @@ class Database {
 		}
 	}
 
+	/**
+	 * Returns true if this database supports (and uses) cascading deletes
+	 */
+	function cascadingDeletes() {
+		return $this->mCascadingDeletes;
+	}
+
+	/**
+	 * Returns true if this database supports (and uses) triggers (e.g. on the page table)
+	 */
+	function cleanupTriggers() {
+		return $this->mCleanupTriggers;
+	}
+
 	/**#@+
 	 * Get function
 	 */
diff --git a/includes/DatabasePostgres.php b/includes/DatabasePostgres.php
index f9c1def569..b0dfb7437a 100644
--- a/includes/DatabasePostgres.php
+++ b/includes/DatabasePostgres.php
@@ -30,8 +30,9 @@ class DatabasePostgres extends Database {
 		}
 		$this->mOut =& $wgOut;
 		$this->mFailFunction = $failFunction;
+		$this->mCascadingDeletes = true;
+		$this->mCleanupTriggers = true;
 		$this->mFlags = $flags;
-
 		$this->open( $server, $user, $password, $dbName);
 
 	}
-- 
2.20.1