[ticket/11040] Add migration to drop postgres search indexes

PHPBB3-11040

phpBB/phpbb/db/migration/data/v310/postgres_fulltext_drop.php

@@ -0,0 +1,47 @@
+<?php
+/**
+*
+* @package migration
+* @copyright (c) 2013 phpBB Group
+* @license http://opensource.org/licenses/gpl-2.0.php GNU General Public License v2
+*
+*/
+
+namespace phpbb\db\migration\data\v310;
+
+class postgres_fulltext_drop extends \phpbb\db\migration\migration
+{
+	public function effectively_installed()
+	{
+		// This migration is irrelevant for all non-PostgreSQL DBMSes.
+		return strpos($this->db->sql_layer, 'postgres') === false;
+	}
+
+	static public function depends_on()
+	{
+		return array(
+			'\phpbb\db\migration\data\v310\dev',
+		);
+	}
+
+	public function update_schema()
+	{
+		/*
+		* Drop FULLTEXT indexes related to PostgreSQL fulltext search.
+		* Doing so is equivalent to dropping the search index from the ACP.
+		* Possibly time-consuming recreation of the search index (i.e.
+		* FULLTEXT indexes) is left as a task to the admin to not
+		* unnecessarily stall the upgrade process. The new search index will
+		* then require about 40% less table space (also see PHPBB3-11040).
+		*/
+		return array(
+			'drop_keys' => array(
+				$this->table_prefix . 'posts' => array(
+					'post_subject',
+					'post_text',
+					'post_content',
+				),
+			),
+		);
+	}
+}