From a7c2180672bbf621333af9c2a380c0f06d17c6d9 Mon Sep 17 00:00:00 2001
From: Scott Taylor <scott.c.taylor@mac.com>
Date: Wed, 4 Jun 2014 05:48:14 +0000
Subject: [PATCH] Fix SQL generation when `meta_query` has an `'relation' =>
 'OR'` for its queries and wants to `'orderby' => 'meta_value'`.

Adds unit test.

Props jackreichert.
Fixes #25538.


Built from https://develop.svn.wordpress.org/trunk@28659


git-svn-id: http://core.svn.wordpress.org/trunk@28477 1a063a9b-81f0-0310-95a4-ce76da25c4cd
---
 wp-includes/meta.php | 17 ++++++++++++++---
 1 file changed, 14 insertions(+), 3 deletions(-)

diff --git a/wp-includes/meta.php b/wp-includes/meta.php
index 1b72ca317a..cb83e4600e 100644
--- a/wp-includes/meta.php
+++ b/wp-includes/meta.php
@@ -972,6 +972,7 @@ class WP_Meta_Query {
 				$where["key-only-$key"] = $wpdb->prepare( "$meta_table.meta_key = %s", trim( $q['key'] ) );
 		}
 
+		$where_meta_key = array();
 		foreach ( $queries as $k => $q ) {
 			$meta_key = isset( $q['key'] ) ? trim( $q['key'] ) : '';
 			$meta_type = $this->get_cast_for_type( isset( $q['type'] ) ? $q['type'] : '' );
@@ -1014,12 +1015,18 @@ class WP_Meta_Query {
 			$join[$i] .= " ON ($primary_table.$primary_id_column = $alias.$meta_id_column)";
 
 			$where[$k] = '';
-			if ( !empty( $meta_key ) )
-				$where[$k] = $wpdb->prepare( "$alias.meta_key = %s", $meta_key );
+			if ( ! empty( $meta_key ) ) {
+				if ( isset( $q['compare'] ) ) {
+					$where_meta_key[$k] = $wpdb->prepare( "$alias.meta_key = %s", $meta_key );
+				} else {
+					$where[$k] = $wpdb->prepare( "$alias.meta_key = %s", $meta_key );
+				}
+			}
 
 			if ( is_null( $meta_value ) ) {
-				if ( empty( $where[$k] ) )
+				if ( empty( $where[$k] ) && empty( $where_meta_key ) ) {
 					unset( $join[$i] );
+				}
 				continue;
 			}
 
@@ -1060,6 +1067,10 @@ class WP_Meta_Query {
 		else
 			$where = ' AND (' . implode( "\n{$this->relation} ", $where ) . ' )';
 
+		if ( ! empty( $where_meta_key ) ) {
+			$where .= "\nAND " . implode( "\nAND ", $where_meta_key );
+		}
+
 		$join = implode( "\n", $join );
 		if ( ! empty( $join ) )
 			$join = ' ' . $join;