From ab6568d056f79d83adc894d561622884b199a551 Mon Sep 17 00:00:00 2001
From: Tim Starling <tstarling@users.mediawiki.org>
Date: Mon, 7 Apr 2008 14:05:12 +0000
Subject: [PATCH] Proposal for method to upgrade the logging table at wikimedia

---
 maintenance/archives/upgradeLogging.php | 181 ++++++++++++++++++++++++
 1 file changed, 181 insertions(+)
 create mode 100644 maintenance/archives/upgradeLogging.php

diff --git a/maintenance/archives/upgradeLogging.php b/maintenance/archives/upgradeLogging.php
new file mode 100644
index 0000000000..254a90c190
--- /dev/null
+++ b/maintenance/archives/upgradeLogging.php
@@ -0,0 +1,181 @@
+<?php
+
+/**
+ * Replication-safe online upgrade script for log_id/log_deleted
+ */
+
+require( dirname(__FILE__).'/../commandLine.inc' );
+
+class UpdateLogging {
+	var $dbw;
+	var $batchSize = 1000;
+	var $minTs = false;
+
+	function execute() {
+		$this->dbw = wfGetDB( DB_MASTER );
+		$logging = $this->dbw->tableName( 'logging' );
+		$logging_1_10 = $this->dbw->tableName( 'logging_1_10' );
+		$logging_pre_1_10 = $this->dbw->tableName( 'logging_pre_1_10' );
+
+		if ( $this->dbw->tableExists( 'logging_pre_1_10' ) && !$this->dbw->tableExists( 'logging' ) ) {
+			# Fix previous aborted run
+			echo "Cleaning up from previous aborted run\n";
+			$this->dbw->query( "RENAME TABLE $logging_pre_1_10 TO $logging", __METHOD__ );
+		}
+
+		if ( $this->dbw->tableExists( 'logging_pre_1_10' ) ) {
+			echo "This script has already been run to completion\n";
+			return;
+		}
+
+		# Create the target table
+		if ( !$this->dbw->tableExists( 'logging_1_10' ) ) {
+			global $wgDBTableOptions;
+
+			$sql = <<<EOT
+CREATE TABLE $logging_1_10 (
+  -- Log ID, for referring to this specific log entry, probably for deletion and such.
+  log_id int unsigned NOT NULL auto_increment,
+
+  -- Symbolic keys for the general log type and the action type
+  -- within the log. The output format will be controlled by the
+  -- action field, but only the type controls categorization.
+  log_type varbinary(10) NOT NULL default '',
+  log_action varbinary(10) NOT NULL default '',
+  
+  -- Timestamp. Duh.
+  log_timestamp binary(14) NOT NULL default '19700101000000',
+  
+  -- The user who performed this action; key to user_id
+  log_user int unsigned NOT NULL default 0,
+  
+  -- Key to the page affected. Where a user is the target,
+  -- this will point to the user page.
+  log_namespace int NOT NULL default 0,
+  log_title varchar(255) binary NOT NULL default '',
+  
+  -- Freeform text. Interpreted as edit history comments.
+  log_comment varchar(255) NOT NULL default '',
+  
+  -- LF separated list of miscellaneous parameters
+  log_params blob NOT NULL,
+
+  -- rev_deleted for logs
+  log_deleted tinyint unsigned NOT NULL default '0',
+
+  PRIMARY KEY log_id (log_id),
+  KEY type_time (log_type, log_timestamp),
+  KEY user_time (log_user, log_timestamp),
+  KEY page_time (log_namespace, log_title, log_timestamp),
+  KEY times (log_timestamp)
+
+) $wgDBTableOptions
+EOT;
+			echo "Creating table logging_1_10\n";
+			$this->dbw->query( $sql, __METHOD__ );
+		}
+
+		# Synchronise the tables
+		echo "Doing initial sync...\n";
+		$this->sync( 'logging', 'logging_1_10' );
+		echo "Sync done\n\n";
+
+		# Rename the old table away
+		echo "Renaming the old table to $logging_pre_1_10\n";
+		$this->dbw->query( "RENAME TABLE $logging TO $logging_pre_1_10", __METHOD__ );
+
+		# Copy remaining old rows
+		# Done before the new table is active so that $copyPos is accurate
+		echo "Doing final sync...\n";
+		$this->sync( 'logging_pre_1_10', 'logging_1_10' );
+
+		# Move the new table in
+		echo "Moving the new table in...\n";
+		$this->dbw->query( "RENAME TABLE $logging_1_10 TO $logging", __METHOD__ );
+		echo "Finished.\n";
+	}
+
+	/**
+	 * Copy all rows from $srcTable to $dstTable
+	 */
+	function sync( $srcTable, $dstTable ) {
+		$batchSize = 1000;
+		$minTs = $this->dbw->selectField( $srcTable, 'MIN(log_timestamp)', false, __METHOD__ );
+		$numRowsCopied = 0;
+		
+		while ( true ) {
+			$maxTs = $this->dbw->selectField( $srcTable, 'MAX(log_timestamp)', false, __METHOD__ );
+			$copyPos = $this->dbw->selectField( $dstTable, 'MAX(log_timestamp)', false, __METHOD__ );
+
+			$percent = ( wfTimestamp( TS_UNIX, $maxTs ) - wfTimestamp( TS_UNIX, $minTs ) )
+				/ wfTimestamp( TS_UNIX, $copyPos ) * 100;
+			printf( "%s  %.2f%%\n", $copyPos, $percent );
+			
+			# Handle all entries with timestamp equal to $copyPos
+			if ( $copyPos !== null ) {
+				$numRowsCopied += $this->copyExactMatch( $srcTable, $dstTable, $copyPos );
+			}
+
+			# Now copy a batch of rows
+			if ( $copyPos === null ) {
+				$conds = false;
+			} else {
+				$conds = array( 'log_timestamp > ' . $this->dbw->addQuotes( $copyPos ) );
+			}
+			$srcRes = $this->dbw->select( $srcTable, '*', $conds, __METHOD__, 
+				array( 'LIMIT' => $batchSize, 'ORDER BY' => 'log_timestamp' ) );
+
+			if ( ! $srcRes->numRows() ) {
+				# All done
+				break;
+			}
+
+			$batch = array();
+			foreach ( $srcRes as $srcRow ) {
+				$batch[] = (array)$srcRow;
+			}
+			$this->dbw->insert( $dstTable, $batch, __METHOD__ );
+			$numRowsCopied += count( $batch );
+
+			wfWaitForSlaves( 5 );
+		}
+		echo "Copied $numRowsCopied rows\n";
+	}
+
+	function copyExactMatch( $srcTable, $dstTable, $copyPos ) {
+		$numRowsCopied = 0;
+		$srcRes = $this->dbw->select( $srcTable, '*', array( 'log_timestamp' => $copyPos ), __METHOD__ );
+		$dstRes = $this->dbw->select( $dstTable, '*', array( 'log_timestamp' => $copyPos ), __METHOD__ );
+
+		if ( $srcRes->numRows() ) {
+			$srcRow = $srcRes->fetchObject();
+			$srcFields = array_keys( (array)$srcRow );
+			$srcRes->seek( 0 );
+			$dstRowsSeen = array();
+
+			# Make a hashtable of rows that already exist in the destination
+			foreach ( $dstRes as $dstRow ) {
+				$reducedDstRow = array();
+				foreach ( $srcFields as $field ) {
+					$reducedDstRow[$field] = $dstRow->$field;
+				}
+				$hash = md5( serialize( $reducedDstRow ) );
+				$dstRowsSeen[$hash] = true;
+			}
+
+			# Copy all the source rows that aren't already in the destination
+			foreach ( $srcRes as $srcRow ) {
+				$hash = md5( serialize( (array)$srcRow ) );
+				if ( !isset( $dstRowsSeen[$hash] ) ) {
+					$this->dbw->insert( $dstTable, (array)$srcRow, __METHOD__ );
+					$numRowsCopied++;
+				}
+			}
+		}
+		return $numRowsCopied;
+	}
+}
+
+$ul = new UpdateLogging;
+$ul->execute();
+
-- 
2.20.1