MDL-31985 convert all existing LOBs

BenKelada · Mar 11, 2012 · 436650b · 436650b
1 parent f13489d
commit 436650b
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Showing 3 changed files with 63 additions and 1 deletion.
diff --git a/lib/db/upgrade.php b/lib/db/upgrade.php
@@ -204,6 +204,14 @@ function xmldb_main_upgrade($oldversion) {
         upgrade_main_savepoint(true, 2012030100.02);
     }
 
+    if ($oldversion < 2012030900.01) {
+        // migrate all texts and binaries to big size - it should be safe to interrupt this and continue later
+        upgrade_mysql_fix_lob_columns();
+
+        // Main savepoint reached
+        upgrade_main_savepoint(true, 2012030900.01);
+    }
+
 
     return true;
 }

diff --git a/lib/db/upgradelib.php b/lib/db/upgradelib.php
@@ -83,3 +83,57 @@ function upgrade_mysql_fix_unsigned_columns() {
         $pbar->update($i, $tablecount, "Converted unsigned columns in MySQL database - $i/$tablecount.");
     }
 }
+
+/**
+ * Migrate all text and binary columns to big size - mysql only.
+ */
+function upgrade_mysql_fix_lob_columns() {
+    // we are not using standard API for changes of column intentionally
+
+    global $DB;
+
+    if ($DB->get_dbfamily() !== 'mysql') {
+        return;
+    }
+
+    $pbar = new progress_bar('mysqlconvertlobs', 500, true);
+
+    $prefix = $DB->get_prefix();
+    $tables = $DB->get_tables();
+    asort($tables);
+
+    $tablecount = count($tables);
+    $i = 0;
+    foreach ($tables as $table) {
+        $i++;
+        // set appropriate timeout - 1 minute per thousand of records should be enough, min 60 minutes just in case
+        $count = $DB->count_records($table, array());
+        $timeout = ($count/1000)*60;
+        $timeout = ($timeout < 60*60) ? 60*60 : (int)$timeout;
+
+        $sql = "SHOW COLUMNS FROM `{{$table}}`";
+        $rs = $DB->get_recordset_sql($sql);
+        foreach ($rs as $column) {
+            upgrade_set_timeout($timeout);
+
+            $column = (object)array_change_key_case((array)$column, CASE_LOWER);
+            if ($column->type === 'tinytext' or $column->type === 'mediumtext' or $column->type === 'text') {
+                $notnull = ($column->null === 'NO') ? 'NOT NULL' : 'NULL';
+                $default = !is_null($column->default) ? "DEFAULT '$column->default'" : '';
+                // primary, unique and inc are not supported for texts
+                $sql = "ALTER TABLE `{$prefix}$table` MODIFY COLUMN `$column->field` LONGTEXT $notnull $default";
+                $DB->change_database_structure($sql);
+            }
+            if ($column->type === 'tinyblob' or $column->type === 'mediumblob' or $column->type === 'blob') {
+                $notnull = ($column->null === 'NO') ? 'NOT NULL' : 'NULL';
+                $default = !is_null($column->default) ? "DEFAULT '$column->default'" : '';
+                // primary, unique and inc are not supported for blobs
+                $sql = "ALTER TABLE `{$prefix}$table` MODIFY COLUMN `$column->field` LONGBLOB $notnull $default";
+                $DB->change_database_structure($sql);
+            }
+        }
+        $rs->close();
+
+        $pbar->update($i, $tablecount, "Converted LOB columns in MySQL database - $i/$tablecount.");
+    }
+}
diff --git a/version.php b/version.php
@@ -30,7 +30,7 @@
 defined('MOODLE_INTERNAL') || die();
 
 
-$version  = 2012030900.00;              // YYYYMMDD      = weekly release date of this DEV branch
+$version  = 2012030900.01;              // YYYYMMDD      = weekly release date of this DEV branch
                                         //         RR    = release increments - 00 in DEV branches
                                         //           .XX = incremental changes