1 files changed, 55 insertions, 0 deletions
diff --git a/phpBB/phpbb/db/migration/data/v32x/user_notifications_table_remove_duplicates.php b/phpBB/phpbb/db/migration/data/v32x/user_notifications_table_remove_duplicates.php
new file mode 100644
index 0000000000..50d0642056
--- /dev/null
+++ b/phpBB/phpbb/db/migration/data/v32x/user_notifications_table_remove_duplicates.php
@@ -0,0 +1,55 @@
+<?php
+/**
+ *
+ * This file is part of the phpBB Forum Software package.
+ *
+ * @copyright (c) phpBB Limited <https://www.phpbb.com>
+ * @license GNU General Public License, version 2 (GPL-2.0)
+ *
+ * For full copyright and license information, please see
+ * the docs/CREDITS.txt file.
+ *
+ */
+
+namespace phpbb\db\migration\data\v32x;
+
+class user_notifications_table_remove_duplicates extends \phpbb\db\migration\migration
+{
+	static public function depends_on()
+	{
+		return array(
+			'\phpbb\db\migration\data\v32x\user_notifications_table_temp_index',
+		);
+	}
+
+	public function update_data()
+	{
+		return array(
+			array('custom', array(array($this, 'remove_duplicates'))),
+		);
+	}
+
+	public function remove_duplicates()
+	{
+		$insert_buffer = new \phpbb\db\sql_insert_buffer($this->db, $this->table_prefix . 'user_notifications');
+
+		$sql = "SELECT item_type, item_id, user_id, method, MAX(notify) AS notify
+				FROM {$this->table_prefix}user_notifications
+				GROUP BY item_type, item_id, user_id, method
+				HAVING COUNT(item_type) > 1";
+
+		$result = $this->sql_query($sql);
+		while ($row = $this->db->sql_fetchrow($result))
+		{
+			// Delete the duplicate entries
+			$this->sql_query("DELETE FROM {$this->table_prefix}user_notifications
+								WHERE user_id = {$row['user_id']}
+								  AND item_type = '{$row['item_type']}'
+								  AND method = '{$row['method']}'");
+
+			// And re-insert as a single one
+			$insert_buffer->insert($row);
+		}
+		$this->db->sql_freeresult($result);
+	}
+}