<?php
# Convert from the old links schema (string->ID) to the new schema (ID->ID)
-# This hasn't been thoroughly tested yet.
-
# The wiki should be put into read-only mode while this script executes
require_once( "commandLine.inc" );
$numRows = $tuplesAdded = $numBadLinks = $curRowsRead = 0; #counters etc
$totalTuplesInserted = 0; # total tuples INSERTed into links_temp
+
$reportCurReadProgress = true; #whether or not to give progress reports while reading IDs from cur table
$curReadReportInterval = 1000; #number of rows between progress reports
+
$reportLinksConvProgress = true; #whether or not to give progress reports during conversion
-$linksConvInsertInterval = 1000; #number of rows between INSERTs and, optionally, reports
+$linksConvInsertInterval = 1000; #number of rows per INSERT
+
$initialRowOffset = 0;
-$finalRowOffset = 0; # not used yet; highest row number from links table to process
-$createTemporaryTable = 1; # create a temporary table to hold new links table during conv process
-$overwriteLinksTable = 1; # overwrite the old links table with the new one
+#$finalRowOffset = 0; # not used yet; highest row number from links table to process
+
+# Overwrite the old links table with the new one. If this is set to false,
+# the new table will be left at links_temp.
+$overwriteLinksTable = true;
+
+# Don't create keys, and so allow duplicates in the new links table.
+# This gives a huge speed improvement for very large links tables which are MyISAM. (What about InnoDB?)
+$noKeys = false;
+
+
+$logPerformance = false; # output performance data to a file
+$perfLogFilename = "convLinksPerf.txt";
+#--------------------------------------------------------------------
$res = wfQuery( "SELECT COUNT(*) AS count FROM links", DB_WRITE );
$row = wfFetchObject($res);
print "Schema already converted\n";
exit;
}
-
+
+ if ( $logPerformance ) { $fh = fopen ( $perfLogFilename, "w" ); }
+ $baseTime = $startTime = getMicroTime();
# Create a title -> cur_id map
- print "Loading IDs from cur table...";
+ print "Loading IDs from cur table...\n";
+ performanceLog ( "Reading $numRows rows from cur table...\n" );
+ performanceLog ( "rows read vs seconds elapsed:\n" );
wfBufferSQLResults( false );
$res = wfQuery( "SELECT cur_namespace,cur_title,cur_id FROM cur", DB_WRITE );
$ids = array();
$curRowsRead++;
if ($reportCurReadProgress) {
if (($curRowsRead % $curReadReportInterval) == 0) {
+ performanceLog( $curRowsRead . " " . (getMicroTime() - $baseTime) . "\n" );
print "\t$curRowsRead rows of cur table read.\n";
}
}
}
wfFreeResult( $res );
wfBufferSQLResults( true );
- print "Finished loading IDs.\n";
- if ( $createTemporaryTable ) {
- # Create temporary table which will become the new links table.
- createTempTable();
- }
-
+ print "Finished loading IDs.\n\n";
+ performanceLog( "Took " . (getMicroTime() - $baseTime) . " seconds to load IDs.\n\n" );
+#--------------------------------------------------------------------
+
# Now, step through the links table (in chunks of $linksConvInsertInterval rows),
# convert, and write to the new table.
+ createTempTable();
+ performanceLog( "Resetting timer.\n\n" );
+ $baseTime = getMicroTime();
print "Processing $numRows rows from links table...\n";
+ performanceLog( "Processing $numRows rows from links table...\n" );
+ performanceLog( "rows inserted vs seconds elapsed:\n" );
+
for ($rowOffset = $initialRowOffset; $rowOffset < $numRows; $rowOffset += $linksConvInsertInterval) {
$sqlRead = "SELECT * FROM links LIMIT $linksConvInsertInterval OFFSET $rowOffset";
$res = wfQuery($sqlRead, DB_READ);
- $sqlWrite = array("INSERT IGNORE INTO links_temp(l_from,l_to) VALUES ");
+ if ( $noKeys ) {
+ $sqlWrite = array("INSERT INTO links_temp(l_from,l_to) VALUES ");
+ } else {
+ $sqlWrite = array("INSERT IGNORE INTO links_temp(l_from,l_to) VALUES ");
+ }
+
$tuplesAdded = 0; # no tuples added to INSERT yet
while ( $row = wfFetchObject($res) ) {
- $fromTitle = $row->l_from;
+ $fromTitle = $row->l_from;
if ( array_key_exists( $fromTitle, $ids ) ) { # valid title
$from = $ids[$fromTitle];
$to = $row->l_to;
wfFreeResult($res);
#print "rowOffset: $rowOffset\ttuplesAdded: $tuplesAdded\tnumBadLinks: $numBadLinks\n";
if ( $tuplesAdded != 0 ) {
- if ($reportLinksConvProgress)
+ if ($reportLinksConvProgress) {
print "Inserting $tuplesAdded tuples into links_temp...";
+ }
wfQuery( implode("",$sqlWrite) , DB_WRITE );
$totalTuplesInserted += $tuplesAdded;
if ($reportLinksConvProgress)
print " done. Total $totalTuplesInserted tuples inserted.\n";
+ performanceLog( $totalTuplesInserted . " " . (getMicroTime() - $baseTime) . "\n" );
}
}
- print "$totalTuplesInserted valid titles and $numBadLinks invalid titles were processed.\n";
+ print "$totalTuplesInserted valid titles and $numBadLinks invalid titles were processed.\n\n";
+ performanceLog( "$totalTuplesInserted valid titles and $numBadLinks invalid titles were processed.\n" );
+ performanceLog( "Total execution time: " . (getMicroTime() - $startTime) . " seconds.\n" );
+ if ( $logPerformance ) { fclose ( $fh ); }
}
+#--------------------------------------------------------------------
if ( $overwriteLinksTable ) {
$dbConn = Database::newFromParams( $wgDBserver, $wgDBadminuser, $wgDBadminpassword, $wgDBname );
# Swap in the new table, and move old links table to links_backup
print "Swapping tables 'links' to 'links_backup'; 'links_temp' to 'links'...";
$dbConn->query( "RENAME TABLE links TO links_backup, links_temp TO links", DB_WRITE );
- print " done.\n";
+ print " done.\n\n";
$dbConn->close();
print "Conversion complete. The old table remains at links_backup;\n";
print "delete at your leisure.\n";
} else {
- print "Conversion complete.\n";
+ print "Conversion complete. The converted table is at links_temp;\n";
+ print "the original links table is unchanged.\n";
}
+#--------------------------------------------------------------------
+
function createTempTable() {
global $wgDBserver, $wgDBadminuser, $wgDBadminpassword, $wgDBname;
+ global $noKeys;
$dbConn = Database::newFromParams( $wgDBserver, $wgDBadminuser, $wgDBadminpassword, $wgDBname );
if (!($dbConn->isOpen())) {
print " done.\n";
print "Creating temporary links table...";
- $dbConn->query( "CREATE TABLE links_temp (
- l_from int(8) unsigned NOT NULL default '0',
- l_to int(8) unsigned NOT NULL default '0',
- UNIQUE KEY l_from(l_from,l_to),
- KEY (l_to))", DB_WRITE);
- print " done.\n";
+ if ( $noKeys ) {
+ $dbConn->query( "CREATE TABLE links_temp ( " .
+ "l_from int(8) unsigned NOT NULL default '0', " .
+ "l_to int(8) unsigned NOT NULL default '0')", DB_WRITE);
+ } else {
+ $dbConn->query( "CREATE TABLE links_temp ( " .
+ "l_from int(8) unsigned NOT NULL default '0', " .
+ "l_to int(8) unsigned NOT NULL default '0', " .
+ "UNIQUE KEY l_from(l_from,l_to), " .
+ "KEY (l_to))", DB_WRITE);
+ }
+ print " done.\n\n";
+}
+
+function performanceLog( $text ) {
+ global $logPerformance, $fh;
+ if ( $logPerformance ) {
+ fwrite( $fh, $text );
+ }
+}
+
+function getMicroTime() { # return time in seconds, with microsecond accuracy
+ list($usec, $sec) = explode(" ", microtime());
+ return ((float)$usec + (float)$sec);
}
?>