3 function convertLinks() {
4 print "Converting links table to ID-ID...\n";
6 global $wgLang, $wgDBserver, $wgDBadminuser, $wgDBadminpassword, $wgDBname;
7 global $noKeys, $logPerformance, $fh;
9 $numRows = $tuplesAdded = $numBadLinks = $curRowsRead = 0; #counters etc
10 $totalTuplesInserted = 0; # total tuples INSERTed into links_temp
12 $reportCurReadProgress = true; #whether or not to give progress reports while reading IDs from cur table
13 $curReadReportInterval = 1000; #number of rows between progress reports
15 $reportLinksConvProgress = true; #whether or not to give progress reports during conversion
16 $linksConvInsertInterval = 1000; #number of rows per INSERT
18 $initialRowOffset = 0;
19 #$finalRowOffset = 0; # not used yet; highest row number from links table to process
21 # Overwrite the old links table with the new one. If this is set to false,
22 # the new table will be left at links_temp.
23 $overwriteLinksTable = true;
25 # Don't create keys, and so allow duplicates in the new links table.
26 # This gives a huge speed improvement for very large links tables which are MyISAM. (What about InnoDB?)
30 $logPerformance = false; # output performance data to a file
31 $perfLogFilename = "convLinksPerf.txt";
32 #--------------------------------------------------------------------
34 $res = wfQuery( "SELECT l_from FROM links LIMIT 1", DB_READ );
35 if ( mysql_field_type( $res, 0 ) == "int" ) {
36 print "Schema already converted\n";
40 $res = wfQuery( "SELECT COUNT(*) AS count FROM links", DB_WRITE );
41 $row = wfFetchObject($res);
42 $numRows = $row->count;
45 if ( $numRows == 0 ) {
46 print "Updating schema (no rows to convert)...\n";
49 if ( $logPerformance ) { $fh = fopen ( $perfLogFilename, "w" ); }
50 $baseTime = $startTime = getMicroTime();
51 # Create a title -> cur_id map
52 print "Loading IDs from cur table...\n";
53 performanceLog ( "Reading $numRows rows from cur table...\n" );
54 performanceLog ( "rows read vs seconds elapsed:\n" );
55 wfBufferSQLResults( false );
56 $res = wfQuery( "SELECT cur_namespace,cur_title,cur_id FROM cur", DB_WRITE );
59 while ( $row = wfFetchObject( $res ) ) {
60 $title = $row->cur_title;
61 if ( $row->cur_namespace ) {
62 $title = $wgLang->getNsText( $row->cur_namespace ) . ":$title";
64 $ids[$title] = $row->cur_id;
66 if ($reportCurReadProgress) {
67 if (($curRowsRead % $curReadReportInterval) == 0) {
68 performanceLog( $curRowsRead . " " . (getMicroTime() - $baseTime) . "\n" );
69 print "\t$curRowsRead rows of cur table read.\n";
74 wfBufferSQLResults( true );
75 print "Finished loading IDs.\n\n";
76 performanceLog( "Took " . (getMicroTime() - $baseTime) . " seconds to load IDs.\n\n" );
77 #--------------------------------------------------------------------
79 # Now, step through the links table (in chunks of $linksConvInsertInterval rows),
80 # convert, and write to the new table.
82 performanceLog( "Resetting timer.\n\n" );
83 $baseTime = getMicroTime();
84 print "Processing $numRows rows from links table...\n";
85 performanceLog( "Processing $numRows rows from links table...\n" );
86 performanceLog( "rows inserted vs seconds elapsed:\n" );
88 for ($rowOffset = $initialRowOffset; $rowOffset < $numRows; $rowOffset += $linksConvInsertInterval) {
89 $sqlRead = "SELECT * FROM links ".wfLimitResult($linksConvInsertInterval,$rowOffset);
90 $res = wfQuery($sqlRead, DB_READ);
92 $sqlWrite = array("INSERT INTO links_temp(l_from,l_to) VALUES ");
94 $sqlWrite = array("INSERT IGNORE INTO links_temp(l_from,l_to) VALUES ");
97 $tuplesAdded = 0; # no tuples added to INSERT yet
98 while ( $row = wfFetchObject($res) ) {
99 $fromTitle = $row->l_from;
100 if ( array_key_exists( $fromTitle, $ids ) ) { # valid title
101 $from = $ids[$fromTitle];
103 if ( $tuplesAdded != 0 ) {
106 $sqlWrite[] = "($from,$to)";
108 } else { # invalid title
113 #print "rowOffset: $rowOffset\ttuplesAdded: $tuplesAdded\tnumBadLinks: $numBadLinks\n";
114 if ( $tuplesAdded != 0 ) {
115 if ($reportLinksConvProgress) {
116 print "Inserting $tuplesAdded tuples into links_temp...";
118 wfQuery( implode("",$sqlWrite) , DB_WRITE );
119 $totalTuplesInserted += $tuplesAdded;
120 if ($reportLinksConvProgress)
121 print " done. Total $totalTuplesInserted tuples inserted.\n";
122 performanceLog( $totalTuplesInserted . " " . (getMicroTime() - $baseTime) . "\n" );
125 print "$totalTuplesInserted valid titles and $numBadLinks invalid titles were processed.\n\n";
126 performanceLog( "$totalTuplesInserted valid titles and $numBadLinks invalid titles were processed.\n" );
127 performanceLog( "Total execution time: " . (getMicroTime() - $startTime) . " seconds.\n" );
128 if ( $logPerformance ) { fclose ( $fh ); }
130 #--------------------------------------------------------------------
132 if ( $overwriteLinksTable ) {
133 $dbConn = Database::newFromParams( $wgDBserver, $wgDBadminuser, $wgDBadminpassword, $wgDBname );
134 if (!($dbConn->isOpen())) {
135 print "Opening connection to database failed.\n";
138 # Check for existing links_backup, and delete it if it exists.
139 print "Dropping backup links table if it exists...";
140 $dbConn->query( "DROP TABLE IF EXISTS links_backup", DB_WRITE);
143 # Swap in the new table, and move old links table to links_backup
144 print "Swapping tables 'links' to 'links_backup'; 'links_temp' to 'links'...";
145 $dbConn->query( "RENAME TABLE links TO links_backup, links_temp TO links", DB_WRITE );
149 print "Conversion complete. The old table remains at links_backup;\n";
150 print "delete at your leisure.\n";
152 print "Conversion complete. The converted table is at links_temp;\n";
153 print "the original links table is unchanged.\n";
157 #--------------------------------------------------------------------
159 function createTempTable() {
160 global $wgDBserver, $wgDBadminuser, $wgDBadminpassword, $wgDBname;
162 $dbConn = Database::newFromParams( $wgDBserver, $wgDBadminuser, $wgDBadminpassword, $wgDBname );
164 if (!($dbConn->isOpen())) {
165 print "Opening connection to database failed.\n";
169 print "Dropping temporary links table if it exists...";
170 $dbConn->query( "DROP TABLE IF EXISTS links_temp", DB_WRITE);
173 print "Creating temporary links table...";
175 $dbConn->query( "CREATE TABLE links_temp ( " .
176 "l_from int(8) unsigned NOT NULL default '0', " .
177 "l_to int(8) unsigned NOT NULL default '0')", DB_WRITE);
179 $dbConn->query( "CREATE TABLE links_temp ( " .
180 "l_from int(8) unsigned NOT NULL default '0', " .
181 "l_to int(8) unsigned NOT NULL default '0', " .
182 "UNIQUE KEY l_from(l_from,l_to), " .
183 "KEY (l_to))", DB_WRITE);
188 function performanceLog( $text ) {
189 global $logPerformance, $fh;
190 if ( $logPerformance ) {
191 fwrite( $fh, $text );
195 function getMicroTime() { # return time in seconds, with microsecond accuracy
196 list($usec, $sec) = explode(" ", microtime());
197 return ((float)$usec + (float)$sec);