maintenance/convertLinks.php

   1 <?php
   2 # Convert from the old links schema (string->ID) to the new schema (ID->ID)
   3 # This hasn't been thoroughly tested yet.
   4
   5 # The wiki should be put into read-only mode while this script executes
   6
   7 include_once( "commandLine.inc" );
   8 # the below should probably be moved into commandLine.inc at some point
   9 include_once( "../AdminSettings.php" );
  10
  11 $numRows = $tuplesAdded = $numBadLinks = $curRowsRead = 0; #counters etc
  12 $totalTuplesInserted = 0; # total tuples INSERTed into links_temp
  13 $reportCurReadProgress = true; #whether or not to give progress reports while reading IDs from cur table
  14 $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 between INSERTs and, optionally, reports
  17 $initialRowOffset = 0;
  18 $finalRowOffset = 0; # not used yet; highest row number from links table to process
  19 $createTemporaryTable = 1; # create a temporary table to hold new links table during conv process
  20 $overwriteLinksTable = 0; # overwrite the old links table with the new one
  21
  22 $res = wfQuery( "SELECT COUNT(*) AS count FROM links", DB_WRITE );
  23 $row = wfFetchObject($res);
  24 $numRows = $row->count;
  25 wfFreeResult( $res );
  26
  27 if ( $numRows == 0 ) {
  28         print "No rows to convert. Updating schema...\n";
  29         createTempTable();
  30 } else {
  31         $row = wfFetchObject( $res );
  32         if ( is_numeric( $row->l_from ) ) {
  33                 print "Schema already converted\n";
  34                 exit;
  35         }
  36
  37         # Create a title -> cur_id map
  38         print "Loading IDs from cur table...";
  39         wfBufferSQLResults( false );
  40         $res = wfQuery( "SELECT cur_namespace,cur_title,cur_id FROM cur", DB_WRITE );
  41         $ids = array();
  42
  43         while ( $row = wfFetchObject( $res ) ) {
  44                 $title = $row->cur_title;
  45                 if ( $row->cur_namespace ) {
  46                         $title = $wgLang->getNsText( $row->cur_namespace ) . ":$title";
  47                 }
  48                 $ids[$title] = $row->cur_id;
  49                 $curRowsRead++;
  50                 if ($reportCurReadProgress) {
  51                         if (($curRowsRead % $curReadReportInterval) == 0) {
  52                                 print "\t$curRowsRead rows of cur table read.\n";
  53                         }
  54                 }
  55         }
  56         wfFreeResult( $res );
  57         wfBufferSQLResults( true );
  58         print "Finished loading IDs.\n";
  59         if ( $createTemporaryTable ) {
  60                 # Create temporary table which will become the new links table.
  61                 createTempTable();
  62         }
  63
  64         # Now, step through the links table (in chunks of $linksConvInsertInterval rows),
  65         # convert, and write to the new table.
  66         print "Processing $numRows rows from links table...\n";
  67         for ($rowOffset = $initialRowOffset; $rowOffset < $numRows; $rowOffset += $linksConvInsertInterval) {
  68                 $sqlRead = "SELECT * FROM links LIMIT $linksConvInsertInterval OFFSET $rowOffset";
  69                 $res = wfQuery($sqlRead, DB_READ);
  70                 $sqlWrite = array("INSERT IGNORE INTO links_temp(l_from,l_to) VALUES ");
  71                 $tuplesAdded = 0; # no tuples added to INSERT yet
  72                 while ( $row = wfFetchObject($res) ) {
  73                         $fromTitle = $row->l_from;
  74                         if ( array_key_exists( $fromTitle, $ids ) ) { # valid title
  75                                 $from = $ids[$fromTitle];
  76                                 $to = $row->l_to;
  77                                 if ( $tuplesAdded != 0 ) {
  78                                         $sqlWrite[] = ",";
  79                                 }
  80                                 $sqlWrite[] = "($from,$to)";
  81                                 $tuplesAdded++;
  82                         } else { # invalid title
  83                                 $numBadLinks++;
  84                         }
  85                 }
  86                 wfFreeResult($res);
  87                 #print "rowOffset: $rowOffset\ttuplesAdded: $tuplesAdded\tnumBadLinks: $numBadLinks\n";
  88                 if ( $tuplesAdded != 0  ) {
  89                         if ($reportLinksConvProgress)
  90                                 print "Inserting $tuplesAdded tuples into links_temp...";
  91                         wfQuery( implode("",$sqlWrite) , DB_WRITE );
  92                         $totalTuplesInserted += $tuplesAdded;
  93                         if ($reportLinksConvProgress)
  94                                 print " done. Total $totalTuplesInserted tuples inserted.\n";
  95                 }
  96         }
  97         print "$totalTuplesInserted valid titles and $numBadLinks invalid titles were processed.\n";
  98 }
  99
 100 if ( $overwriteLinksTable ) {
 101         $dbConn = Database::newFromParams( $wgDBserver, $wgDBadminuser, $wgDBadminpassword, $wgDBname );
 102         if (!($dbConn->isOpen())) {
 103                 print "Opening connection to database failed.\n";
 104                 exit;
 105         }
 106         # Check for existing links_backup, and delete it if it exists.
 107         print "Dropping backup links table if it exists...";
 108         $dbConn->query( "DROP TABLE IF EXISTS links_backup", DB_WRITE);
 109         print " done.\n";
 110
 111         # Swap in the new table, and move old links table to links_backup
 112         print "Swapping tables 'links' to 'links_backup'; 'links_temp' to 'links'...";
 113         $dbConn->query( "RENAME TABLE links TO links_backup, links_temp TO links", DB_WRITE );
 114         print " done.\n";
 115
 116         $dbConn->close();
 117         print "Conversion complete. The old table remains at links_backup;\n";
 118         print "delete at your leisure.\n";
 119 } else {
 120         print "Conversion complete.\n";
 121 }
 122
 123 function createTempTable() {
 124         global $wgDBserver, $wgDBadminuser, $wgDBadminpassword, $wgDBname;
 125         $dbConn = Database::newFromParams( $wgDBserver, $wgDBadminuser, $wgDBadminpassword, $wgDBname );
 126
 127         if (!($dbConn->isOpen())) {
 128                 print "Opening connection to database failed.\n";
 129                 exit;
 130         }
 131
 132         print "Dropping temporary links table if it exists...";
 133         $dbConn->query( "DROP TABLE IF EXISTS links_temp", DB_WRITE);
 134         print " done.\n";
 135
 136         print "Creating temporary links table...";
 137         $dbConn->query( "CREATE TABLE links_temp (
 138           l_from int(8) unsigned NOT NULL default '0',
 139           l_to int(8) unsigned NOT NULL default '0',
 140           UNIQUE KEY l_from(l_from,l_to),
 141           KEY (l_to))", DB_WRITE);
 142         print " done.\n";
 143 }
 144 ?>