From 267aa870d32fe7e104052f10eba019690a56b3d3 Mon Sep 17 00:00:00 2001
From: Leon Stringer <leon.stringer@ntlworld.com>
Date: Wed, 19 May 2021 08:27:19 +0100
Subject: [PATCH] MDL-71476 core_cli: Remove MyISAM migration

Remove support for migrating MySQL databases using the old MyISAM storage
engine to the InnoDB storage engine.  MyISAM was supported up to Moodle
2.8 (dropped in 2.9: MDL-46064).  Beyond Moodle 3.3 -- the highest version
that can upgrade from 2.8 -- this functionality was no longer applicable.
---
 admin/cli/mysql_engine.php | 180 -------------------------------------
 1 file changed, 180 deletions(-)
 delete mode 100644 admin/cli/mysql_engine.php

diff --git a/admin/cli/mysql_engine.php b/admin/cli/mysql_engine.php
deleted file mode 100644
index d392b0b6f71..00000000000
--- a/admin/cli/mysql_engine.php
+++ /dev/null
@@ -1,180 +0,0 @@
-<?php
-
-// This file is part of Moodle - http://moodle.org/
-//
-// Moodle is free software: you can redistribute it and/or modify
-// it under the terms of the GNU General Public License as published by
-// the Free Software Foundation, either version 3 of the License, or
-// (at your option) any later version.
-//
-// Moodle is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-// GNU General Public License for more details.
-//
-// You should have received a copy of the GNU General Public License
-// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
-
-/**
- * MySQL engine conversion tool.
- *
- * @package    core
- * @subpackage cli
- * @copyright  2009 Petr Skoda (http://skodak.org)
- * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
- */
-
-define('CLI_SCRIPT', true);
-
-require(__DIR__.'/../../config.php');
-require_once($CFG->libdir.'/clilib.php');      // cli only functions
-
-if ($DB->get_dbfamily() !== 'mysql') {
-    cli_error('This function is designed for MySQL databases only!');
-}
-
-// now get cli options
-list($options, $unrecognized) = cli_get_params(array('help'=>false, 'list'=>false, 'engine'=>false, 'available'=>false),
-                                               array('h'=>'help', 'l'=>'list', 'a'=>'available'));
-
-if ($unrecognized) {
-    $unrecognized = implode("\n  ", $unrecognized);
-    cli_error(get_string('cliunknowoption', 'admin', $unrecognized));
-}
-
-$help =
-"MySQL engine conversions script.
-
-It is recommended to stop the web server before the conversion.
-Do not use MyISAM if possible, because it is not ACID compliant
-and does not support transactions.
-
-Options:
---engine=ENGINE       Convert MySQL tables to different engine
--l, --list            Show table information
--a, --available       Show list of available engines
--h, --help            Print out this help
-
-Example:
-\$sudo -u www-data /usr/bin/php admin/cli/mysql_engine.php --engine=InnoDB
-";
-
-if (!empty($options['engine'])) {
-    $engines = mysql_get_engines();
-    $engine = clean_param($options['engine'], PARAM_ALPHA);
-    if (!isset($engines[strtoupper($engine)])) {
-        cli_error("Error: engine '$engine' is not available on this server!");
-    }
-
-    echo "Converting tables to '$engine' for $CFG->wwwroot:\n";
-    $prefix = $DB->get_prefix();
-    $prefix = str_replace('_', '\\_', $prefix);
-    $sql = "SHOW TABLE STATUS WHERE Name LIKE BINARY '$prefix%'";
-    $rs = $DB->get_recordset_sql($sql);
-    $converted = 0;
-    $skipped   = 0;
-    $errors    = 0;
-    foreach ($rs as $table) {
-        if (strtoupper($table->engine) === strtoupper($engine)) {
-            $newengine = mysql_get_table_engine($table->name);
-            echo str_pad($table->name, 40). " - NO CONVERSION NEEDED ($newengine)\n";
-            $skipped++;
-            continue;
-        }
-        echo str_pad($table->name, 40). " - ";
-
-        try {
-            $DB->change_database_structure("ALTER TABLE {$table->name} ENGINE = $engine");
-            $newengine = mysql_get_table_engine($table->name);
-            if (strtoupper($newengine) !== strtoupper($engine)) {
-                echo "ERROR ($newengine)\n";
-                $errors++;
-                continue;
-            }
-            echo "DONE ($newengine)\n";
-            $converted++;
-        } catch (moodle_exception $e) {
-            echo $e->getMessage()."\n";
-            $errors++;
-            continue;
-        }
-    }
-    $rs->close();
-    echo "Converted: $converted, skipped: $skipped, errors: $errors\n";
-    exit(0); // success
-
-} else if (!empty($options['list'])) {
-    echo "List of tables for $CFG->wwwroot:\n";
-    $prefix = $DB->get_prefix();
-    $prefix = str_replace('_', '\\_', $prefix);
-    $sql = "SHOW TABLE STATUS WHERE Name LIKE BINARY '$prefix%'";
-    $rs = $DB->get_recordset_sql($sql);
-    $counts = array();
-    foreach ($rs as $table) {
-        if (isset($counts[$table->engine])) {
-            $counts[$table->engine]++;
-        } else {
-            $counts[$table->engine] = 1;
-        }
-        echo str_pad($table->engine, 10);
-        echo $table->name .  "\n";
-    }
-    $rs->close();
-
-    echo "\n";
-    echo "Table engines summary for $CFG->wwwroot:\n";
-    foreach ($counts as $engine => $count) {
-        echo "$engine: $count\n";
-    }
-    exit(0); // success
-
-} else if (!empty($options['available'])) {
-    echo "List of available MySQL engines for $CFG->wwwroot:\n";
-    $engines = mysql_get_engines();
-    foreach ($engines as $engine) {
-        echo " $engine\n";
-    }
-    die;
-
-} else {
-    echo $help;
-    die;
-}
-
-
-
-// ========== Some functions ==============
-
-function mysql_get_engines() {
-    global $DB;
-
-    $sql = "SHOW Engines";
-    $rs = $DB->get_recordset_sql($sql);
-    $engines = array();
-    foreach ($rs as $engine) {
-        if (strtoupper($engine->support) !== 'YES' and strtoupper($engine->support) !== 'DEFAULT') {
-            continue;
-        }
-        $engines[strtoupper($engine->engine)] = $engine->engine;
-        if (strtoupper($engine->support) === 'DEFAULT') {
-            $engines[strtoupper($engine->engine)] .= ' (default)';
-        }
-    }
-    $rs->close();
-
-    return $engines;
-}
-
-function mysql_get_table_engine($tablename) {
-    global $DB;
-
-    $engine = null;
-    $sql = "SHOW TABLE STATUS WHERE Name = '$tablename'"; // no special chars expected here
-    $rs = $DB->get_recordset_sql($sql);
-    if ($rs->valid()) {
-        $record = $rs->current();
-        $engine = $record->engine;
-    }
-    $rs->close();
-    return $engine;
-}