Add emergency script to kill all chamilo-user's database queries

tests/scripts/kill_all_queries.php

@@ -0,0 +1,22 @@
+<?php
+/**
+ * This script kills all queries to which the Chamilo database user has access
+ * through processlist.
+ * Use only when you have an impossible situation with an urgent need to
+ * restart or stop the database, and it just won't stop because it want to
+ * finish queries first, and these queries are waiting for a lock on a table
+ * that seems to never free itself.
+ * In this case, disable the exit(); line below, run this script and then you
+ * should be able to quickly restart your database.
+ */
+exit;
+require_once '../../main/inc/global.inc.php';
+$result = Database::query("SHOW FULL PROCESSLIST");
+while ($row=Database::fetch_array($result)) {
+    $process_id=$row["Id"];
+    if ($row["Time"] > 200 ) {
+        $sql="KILL $process_id";
+        Database::query($sql);
+    }
+}
+echo "All queries by this user have been killed".PHP_EOL;