From 0b0c0c7e89cbee8e57eb9caaba92bda246f6cb49 Mon Sep 17 00:00:00 2001
From: Jakub Vrana <jakub@vrana.cz>
Date: Tue, 18 Nov 2014 09:50:02 -0800
Subject: [PATCH] Don't alter table comment if not changed (was crashing MySQL
 Cluster)

---
 adminer/create.inc.php        |  2 +-
 adminer/drivers/mysql.inc.php | 10 ++++++----
 changes.txt                   |  1 +
 3 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/adminer/create.inc.php b/adminer/create.inc.php
index c0e636a9..d813dbb6 100644
--- a/adminer/create.inc.php
+++ b/adminer/create.inc.php
@@ -107,7 +107,7 @@ if ($_POST && !process_fields($row["fields"]) && !$error) {
 			$name,
 			($jush == "sqlite" && ($use_all_fields || $foreign) ? $all_fields : $fields),
 			$foreign,
-			$row["Comment"],
+			($row["Comment"] != $table_status["Comment"] ? $row["Comment"] : null),
 			($row["Engine"] && $row["Engine"] != $table_status["Engine"] ? $row["Engine"] : ""),
 			($row["Collation"] && $row["Collation"] != $table_status["Collation"] ? $row["Collation"] : ""),
 			($row["Auto_increment"] != "" ? +$row["Auto_increment"] : ""),
diff --git a/adminer/drivers/mysql.inc.php b/adminer/drivers/mysql.inc.php
index 8705f5bb..3ca7abb9 100644
--- a/adminer/drivers/mysql.inc.php
+++ b/adminer/drivers/mysql.inc.php
@@ -662,20 +662,22 @@ if (!defined("DRIVER")) {
 			);
 		}
 		$alter = array_merge($alter, $foreign);
-		$status = "COMMENT=" . q($comment)
+		$status = ($comment !== null ? " COMMENT=" . q($comment) : "")
 			. ($engine ? " ENGINE=" . q($engine) : "")
 			. ($collation ? " COLLATE " . q($collation) : "")
 			. ($auto_increment != "" ? " AUTO_INCREMENT=$auto_increment" : "")
 			. $partitioning
 		;
 		if ($table == "") {
-			return queries("CREATE TABLE " . table($name) . " (\n" . implode(",\n", $alter) . "\n) $status");
+			return queries("CREATE TABLE " . table($name) . " (\n" . implode(",\n", $alter) . "\n)$status");
 		}
 		if ($table != $name) {
 			$alter[] = "RENAME TO " . table($name);
 		}
-		$alter[] = $status;
-		return queries("ALTER TABLE " . table($table) . "\n" . implode(",\n", $alter));
+		if ($status) {
+			$alter[] = ltrim($status);
+		}
+		return $alter ? queries("ALTER TABLE " . table($table) . "\n" . implode(",\n", $alter)) : true;
 	}
 
 	/** Run commands to alter indexes
diff --git a/changes.txt b/changes.txt
index 95fca169..fce223da 100644
--- a/changes.txt
+++ b/changes.txt
@@ -7,6 +7,7 @@ Specify encoding for PHP 5.6 with invalid default_charset
 Fix saving NULL value, bug since Adminer 4.0.3
 Send 403 for auth error
 Report offline and other AJAX errors (bug #419)
+Don't alter table comment if not changed
 Add links to documentation on table status page
 MySQL: Use utf8mb4 if available
 MySQL: Support foreign keys in NDB storage