From 31f8f61d0e59d6cd79489455218c44b8de170814 Mon Sep 17 00:00:00 2001
From: Jakub Vrana <jakub@vrana.cz>
Date: Mon, 10 Mar 2025 21:01:21 +0100
Subject: [PATCH] MySQL, MariaDB: Fix default values with ' (fix #895)

---
 adminer/drivers/mysql.inc.php | 22 ++++++++++++++++------
 changes.txt                   |  1 +
 2 files changed, 17 insertions(+), 6 deletions(-)

diff --git a/adminer/drivers/mysql.inc.php b/adminer/drivers/mysql.inc.php
index 1ca3cde9..236602d4 100644
--- a/adminer/drivers/mysql.inc.php
+++ b/adminer/drivers/mysql.inc.php
@@ -587,15 +587,28 @@ if (!defined('Adminer\DRIVER')) {
 	* @return array [$name => ["field" => , "full_type" => , "type" => , "length" => , "unsigned" => , "default" => , "null" => , "auto_increment" => , "on_update" => , "collation" => , "privileges" => , "comment" => , "primary" => , "generated" => ]]
 	*/
 	function fields($table) {
+		global $connection;
+		$maria = preg_match('~MariaDB~', $connection->server_info);
 		$return = array();
 		foreach (get_rows("SELECT * FROM information_schema.COLUMNS WHERE TABLE_SCHEMA = DATABASE() AND TABLE_NAME = " . q($table) . " ORDER BY ORDINAL_POSITION") as $row) {
 			$field = $row["COLUMN_NAME"];
-			$default = $row["COLUMN_DEFAULT"];
 			$type = $row["COLUMN_TYPE"];
+			$generation = $row["GENERATION_EXPRESSION"];
 			$extra = $row["EXTRA"];
 			// https://mariadb.com/kb/en/library/show-columns/, https://github.com/vrana/adminer/pull/359#pullrequestreview-276677186
 			preg_match('~^(VIRTUAL|PERSISTENT|STORED)~', $extra, $generated);
 			preg_match('~^([^( ]+)(?:\((.+)\))?( unsigned)?( zerofill)?$~', $type, $match);
+			$default = $row["COLUMN_DEFAULT"];
+			$is_text = preg_match('~text~', $match[1]);
+			if (!$maria && $is_text) {
+				// default value a'b of text column is stored as _utf8mb4\'a\\\'b\' in MySQL
+				$default = preg_replace("~^(_\w+)?('.*')$~", '\2', stripslashes($default));
+			}
+			if ($maria || $is_text) {
+				$default = preg_replace_callback("~^'(.*)'$~", function ($match) {
+					return str_replace("''", "'", stripslashes($match[1]));
+				}, $default);
+			}
 			$return[$field] = array(
 				"field" => $field,
 				"full_type" => $type,
@@ -603,11 +616,8 @@ if (!defined('Adminer\DRIVER')) {
 				"length" => $match[2],
 				"unsigned" => ltrim($match[3] . $match[4]),
 				"default" => ($generated
-					? $row["GENERATION_EXPRESSION"]
-					: ($default != "" || preg_match("~char|set~", $match[1])
-						? (preg_match('~text~', $match[1]) ? stripslashes(preg_replace("~^'(.*)'\$~", '\1', $default)) : $default)
-						: null
-					)
+					? ($maria ? $generation : stripslashes($generation))
+					: ($default != "" || preg_match("~char|set~", $match[1]) ? $default : null)
 				),
 				"null" => ($row["IS_NULLABLE"] == "YES"),
 				"auto_increment" => ($extra == "auto_increment"),
diff --git a/changes.txt b/changes.txt
index a77bce59..a8d65b43 100644
--- a/changes.txt
+++ b/changes.txt
@@ -2,6 +2,7 @@ Adminer dev:
 Fix gzip export (bug #896)
 Fix importing multiple SQL files not terminated by semicolon
 Use <datalist> for altering collations
+MySQL, MariaDB: Fix default values with ' (bug #895)
 MariaDB: Fix creating and altering generated columns (bug #897)
 
 Adminer 5.0.2 (released 2025-03-10):