From 511a8bae34ebf0a91b54877828f75065c570b705 Mon Sep 17 00:00:00 2001
From: vrana <jakubv@fb.com>
Date: Thu, 4 Oct 2012 14:49:23 -0700
Subject: [PATCH] Optimize feed query

Summary:
This was killing us. `EXPLAIN` after:

<table>
<tr><th>id</th><th>select_type</th><th>table</th><th>type</th><th>possible_keys</th><th>key</th><th>key_len</th><th>ref</th><th>rows</th><th>Extra</th></tr>
<tr><td>1</td><td>SIMPLE</td><td>story</td><td>index</td><td>chronologicalKey</td><td>chronologicalKey</td><td>8</td><td></td><td>201</td><td> </td></tr>
<tr><td>1</td><td>SIMPLE</td><td>ref</td><td>ref</td><td>chronologicalKey</td><td>chronologicalKey</td><td>8</td><td>phabricator_feed.story.chronologicalKey</td><td>1</td><td>Using index</td></tr>
</table>

Test Plan: /feed/

Reviewers: epriestley

Reviewed By: epriestley

CC: aran, Korvin

Differential Revision: https://secure.phabricator.com/D3628
---
 .../controller/PhabricatorDirectoryMainController.php     | 1 +
 src/applications/feed/PhabricatorFeedQuery.php            | 8 ++++++--
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/src/applications/directory/controller/PhabricatorDirectoryMainController.php b/src/applications/directory/controller/PhabricatorDirectoryMainController.php
index 43c29cbe99..76b8d5d198 100644
--- a/src/applications/directory/controller/PhabricatorDirectoryMainController.php
+++ b/src/applications/directory/controller/PhabricatorDirectoryMainController.php
@@ -139,6 +139,7 @@ final class PhabricatorDirectoryMainController
 
     $filter = $subnav->selectFilter($this->subfilter, 'all');
 
+    $view = null;
     switch ($filter) {
       case 'all':
         $view = $this->buildFeedView(array());
diff --git a/src/applications/feed/PhabricatorFeedQuery.php b/src/applications/feed/PhabricatorFeedQuery.php
index 25a58a8eda..2c954c8b49 100644
--- a/src/applications/feed/PhabricatorFeedQuery.php
+++ b/src/applications/feed/PhabricatorFeedQuery.php
@@ -76,11 +76,15 @@ final class PhabricatorFeedQuery
   private function buildGroupClause(AphrontDatabaseConnection $conn_r) {
     return qsprintf(
       $conn_r,
-      'GROUP BY ref.chronologicalKey');
+      'GROUP BY '.($this->filterPHIDs
+        ? 'ref.chronologicalKey'
+        : 'story.chronologicalKey'));
   }
 
   protected function getPagingColumn() {
-    return 'ref.chronologicalKey';
+    return ($this->filterPHIDs
+      ? 'ref.chronologicalKey'
+      : 'story.chronologicalKey');
   }
 
   protected function getPagingValue($item) {