diff --git a/src/applications/diffusion/query/DiffusionCommitQuery.php b/src/applications/diffusion/query/DiffusionCommitQuery.php
index 8abb67b99f..22331e8510 100644
--- a/src/applications/diffusion/query/DiffusionCommitQuery.php
+++ b/src/applications/diffusion/query/DiffusionCommitQuery.php
@@ -1,566 +1,566 @@
 <?php
 
 final class DiffusionCommitQuery
   extends PhabricatorCursorPagedPolicyAwareQuery {
 
   private $ids;
   private $phids;
   private $authorPHIDs;
   private $defaultRepository;
   private $identifiers;
   private $repositoryIDs;
   private $repositoryPHIDs;
   private $identifierMap;
 
   private $needAuditRequests;
   private $auditIDs;
   private $auditorPHIDs;
   private $auditAwaitingUser;
   private $auditStatus;
 
   const AUDIT_STATUS_ANY       = 'audit-status-any';
   const AUDIT_STATUS_OPEN      = 'audit-status-open';
   const AUDIT_STATUS_CONCERN   = 'audit-status-concern';
   const AUDIT_STATUS_ACCEPTED  = 'audit-status-accepted';
   const AUDIT_STATUS_PARTIAL   = 'audit-status-partial';
 
   private $needCommitData;
 
   public function withIDs(array $ids) {
     $this->ids = $ids;
     return $this;
   }
 
   public function withPHIDs(array $phids) {
     $this->phids = $phids;
     return $this;
   }
 
   public function withAuthorPHIDs(array $phids) {
     $this->authorPHIDs = $phids;
     return $this;
   }
 
   /**
    * Load commits by partial or full identifiers, e.g. "rXab82393", "rX1234",
    * or "a9caf12". When an identifier matches multiple commits, they will all
    * be returned; callers should be prepared to deal with more results than
    * they queried for.
    */
   public function withIdentifiers(array $identifiers) {
     $this->identifiers = $identifiers;
     return $this;
   }
 
   /**
    * Look up commits in a specific repository. This is a shorthand for calling
    * @{method:withDefaultRepository} and @{method:withRepositoryIDs}.
    */
   public function withRepository(PhabricatorRepository $repository) {
     $this->withDefaultRepository($repository);
     $this->withRepositoryIDs(array($repository->getID()));
     return $this;
   }
 
   /**
    * Look up commits in a specific repository. Prefer
    * @{method:withRepositoryIDs}; the underyling table is keyed by ID such
    * that this method requires a separate initial query to map PHID to ID.
    */
   public function withRepositoryPHIDs(array $phids) {
     $this->repositoryPHIDs = $phids;
   }
 
   /**
    * If a default repository is provided, ambiguous commit identifiers will
    * be assumed to belong to the default repository.
    *
    * For example, "r123" appearing in a commit message in repository X is
    * likely to be unambiguously "rX123". Normally the reference would be
    * considered ambiguous, but if you provide a default repository it will
    * be correctly resolved.
    */
   public function withDefaultRepository(PhabricatorRepository $repository) {
     $this->defaultRepository = $repository;
     return $this;
   }
 
   public function withRepositoryIDs(array $repository_ids) {
     $this->repositoryIDs = $repository_ids;
     return $this;
   }
 
   public function needCommitData($need) {
     $this->needCommitData = $need;
     return $this;
   }
 
   public function needAuditRequests($need) {
     $this->needAuditRequests = $need;
     return $this;
   }
 
   /**
    * Returns true if we should join the audit table, either because we're
    * interested in the information if it's available or because matching rows
    * must always have it.
    */
   private function shouldJoinAudits() {
     return $this->auditStatus ||
            $this->rowsMustHaveAudits();
   }
 
   /**
    * Return true if we should `JOIN` (vs `LEFT JOIN`) the audit table, because
    * matching commits will always have audit rows.
    */
   private function rowsMustHaveAudits() {
     return
       $this->auditIDs ||
       $this->auditorPHIDs ||
       $this->auditAwaitingUser;
   }
 
   public function withAuditIDs(array $ids) {
     $this->auditIDs = $ids;
     return $this;
   }
 
   public function withAuditorPHIDs(array $auditor_phids) {
     $this->auditorPHIDs = $auditor_phids;
     return $this;
   }
 
   public function withAuditAwaitingUser(PhabricatorUser $user) {
     $this->auditAwaitingUser = $user;
     return $this;
   }
 
   public function withAuditStatus($status) {
     $this->auditStatus = $status;
     return $this;
   }
 
   public function getIdentifierMap() {
     if ($this->identifierMap === null) {
       throw new Exception(
         'You must execute() the query before accessing the identifier map.');
     }
     return $this->identifierMap;
   }
 
-  protected function getPagingColumn() {
-    return 'commit.id';
+  protected function getPrimaryTableAlias() {
+    return 'commit';
   }
 
   protected function willExecute() {
     if ($this->identifierMap === null) {
       $this->identifierMap = array();
     }
   }
 
   protected function loadPage() {
     $table = new PhabricatorRepositoryCommit();
     $conn_r = $table->establishConnection('r');
 
     $data = queryfx_all(
       $conn_r,
       'SELECT commit.* FROM %T commit %Q %Q %Q %Q %Q',
       $table->getTableName(),
       $this->buildJoinClause($conn_r),
       $this->buildWhereClause($conn_r),
       $this->buildGroupClause($conn_r),
       $this->buildOrderClause($conn_r),
       $this->buildLimitClause($conn_r));
 
     return $table->loadAllFromArray($data);
   }
 
   protected function willFilterPage(array $commits) {
     $repository_ids = mpull($commits, 'getRepositoryID', 'getRepositoryID');
     $repos = id(new PhabricatorRepositoryQuery())
       ->setViewer($this->getViewer())
       ->withIDs($repository_ids)
       ->execute();
 
     $min_qualified = PhabricatorRepository::MINIMUM_QUALIFIED_HASH;
     $result = array();
 
     foreach ($commits as $key => $commit) {
       $repo = idx($repos, $commit->getRepositoryID());
       if ($repo) {
         $commit->attachRepository($repo);
       } else {
         unset($commits[$key]);
         continue;
       }
 
       // Build the identifierMap
       if ($this->identifiers !== null) {
         $ids = array_fuse($this->identifiers);
         $prefixes = array(
           'r'.$commit->getRepository()->getCallsign(),
           'r'.$commit->getRepository()->getCallsign().':',
           'R'.$commit->getRepository()->getID().':',
           '', // No prefix is valid too and will only match the commitIdentifier
         );
         $suffix = $commit->getCommitIdentifier();
 
         if ($commit->getRepository()->isSVN()) {
           foreach ($prefixes as $prefix) {
             if (isset($ids[$prefix.$suffix])) {
               $result[$prefix.$suffix][] = $commit;
             }
           }
         } else {
           // This awkward construction is so we can link the commits up in O(N)
           // time instead of O(N^2).
           for ($ii = $min_qualified; $ii <= strlen($suffix); $ii++) {
             $part = substr($suffix, 0, $ii);
             foreach ($prefixes as $prefix) {
               if (isset($ids[$prefix.$part])) {
                 $result[$prefix.$part][] = $commit;
               }
             }
           }
         }
       }
     }
 
     if ($result) {
       foreach ($result as $identifier => $matching_commits) {
         if (count($matching_commits) == 1) {
           $result[$identifier] = head($matching_commits);
         } else {
           // This reference is ambiguous (it matches more than one commit) so
           // don't link it.
           unset($result[$identifier]);
         }
       }
       $this->identifierMap += $result;
     }
 
     return $commits;
   }
 
   protected function didFilterPage(array $commits) {
     if ($this->needCommitData) {
       $data = id(new PhabricatorRepositoryCommitData())->loadAllWhere(
         'commitID in (%Ld)',
         mpull($commits, 'getID'));
       $data = mpull($data, null, 'getCommitID');
       foreach ($commits as $commit) {
         $commit_data = idx($data, $commit->getID());
         if (!$commit_data) {
           $commit_data = new PhabricatorRepositoryCommitData();
         }
         $commit->attachCommitData($commit_data);
       }
     }
 
     // TODO: This should just be `needAuditRequests`, not `shouldJoinAudits()`,
     // but leave that for a future diff.
 
     if ($this->needAuditRequests || $this->shouldJoinAudits()) {
       $requests = id(new PhabricatorRepositoryAuditRequest())->loadAllWhere(
         'commitPHID IN (%Ls)',
         mpull($commits, 'getPHID'));
 
       $requests = mgroup($requests, 'getCommitPHID');
       foreach ($commits as $commit) {
         $audit_requests = idx($requests, $commit->getPHID(), array());
         $commit->attachAudits($audit_requests);
         foreach ($audit_requests as $audit_request) {
           $audit_request->attachCommit($commit);
         }
       }
     }
 
     return $commits;
   }
 
   private function buildWhereClause(AphrontDatabaseConnection $conn_r) {
     $where = array();
 
     if ($this->repositoryPHIDs !== null) {
       $map_repositories = id (new PhabricatorRepositoryQuery())
         ->setViewer($this->getViewer())
         ->withPHIDs($this->repositoryPHIDs)
         ->execute();
 
       if (!$map_repositories) {
         throw new PhabricatorEmptyQueryException();
       }
       $repository_ids = mpull($map_repositories, 'getID');
       if ($this->repositoryIDs !== null) {
         $repository_ids = array_merge($repository_ids, $this->repositoryIDs);
       }
       $this->withRepositoryIDs($repository_ids);
     }
 
     if ($this->ids !== null) {
       $where[] = qsprintf(
         $conn_r,
         'commit.id IN (%Ld)',
         $this->ids);
     }
 
     if ($this->phids !== null) {
       $where[] = qsprintf(
         $conn_r,
         'commit.phid IN (%Ls)',
         $this->phids);
     }
 
     if ($this->repositoryIDs !== null) {
       $where[] = qsprintf(
         $conn_r,
         'commit.repositoryID IN (%Ld)',
         $this->repositoryIDs);
     }
 
     if ($this->authorPHIDs !== null) {
       $where[] = qsprintf(
         $conn_r,
         'commit.authorPHID IN (%Ls)',
         $this->authorPHIDs);
     }
 
     if ($this->identifiers !== null) {
       $min_unqualified = PhabricatorRepository::MINIMUM_UNQUALIFIED_HASH;
       $min_qualified   = PhabricatorRepository::MINIMUM_QUALIFIED_HASH;
 
       $refs = array();
       $bare = array();
       foreach ($this->identifiers as $identifier) {
         $matches = null;
         preg_match('/^(?:[rR]([A-Z]+:?|[0-9]+:))?(.*)$/',
           $identifier, $matches);
         $repo = nonempty(rtrim($matches[1], ':'), null);
         $commit_identifier = nonempty($matches[2], null);
 
         if ($repo === null) {
           if ($this->defaultRepository) {
             $repo = $this->defaultRepository->getCallsign();
           }
         }
 
         if ($repo === null) {
           if (strlen($commit_identifier) < $min_unqualified) {
             continue;
           }
           $bare[] = $commit_identifier;
         } else {
           $refs[] = array(
             'callsign' => $repo,
             'identifier' => $commit_identifier,
           );
         }
       }
 
       $sql = array();
 
       foreach ($bare as $identifier) {
         $sql[] = qsprintf(
           $conn_r,
           '(commit.commitIdentifier LIKE %> AND '.
           'LENGTH(commit.commitIdentifier) = 40)',
           $identifier);
       }
 
       if ($refs) {
         $callsigns = ipull($refs, 'callsign');
 
         $repos = id(new PhabricatorRepositoryQuery())
           ->setViewer($this->getViewer())
           ->withIdentifiers($callsigns);
         $repos->execute();
 
         $repos = $repos->getIdentifierMap();
 
         foreach ($refs as $key => $ref) {
           $repo = idx($repos, $ref['callsign']);
 
           if (!$repo) {
             continue;
           }
 
           if ($repo->isSVN()) {
             if (!ctype_digit($ref['identifier'])) {
               continue;
             }
             $sql[] = qsprintf(
               $conn_r,
               '(commit.repositoryID = %d AND commit.commitIdentifier = %s)',
               $repo->getID(),
               // NOTE: Because the 'commitIdentifier' column is a string, MySQL
               // ignores the index if we hand it an integer. Hand it a string.
               // See T3377.
               (int)$ref['identifier']);
           } else {
             if (strlen($ref['identifier']) < $min_qualified) {
               continue;
             }
             $sql[] = qsprintf(
               $conn_r,
               '(commit.repositoryID = %d AND commit.commitIdentifier LIKE %>)',
               $repo->getID(),
               $ref['identifier']);
           }
         }
       }
 
       if (!$sql) {
         // If we discarded all possible identifiers (e.g., they all referenced
         // bogus repositories or were all too short), make sure the query finds
         // nothing.
         throw new PhabricatorEmptyQueryException(
           pht('No commit identifiers.'));
       }
 
       $where[] = '('.implode(' OR ', $sql).')';
     }
 
     if ($this->auditIDs !== null) {
       $where[] = qsprintf(
         $conn_r,
         'audit.id IN (%Ld)',
         $this->auditIDs);
     }
 
     if ($this->auditorPHIDs !== null) {
       $where[] = qsprintf(
         $conn_r,
         'audit.auditorPHID IN (%Ls)',
         $this->auditorPHIDs);
     }
 
     if ($this->auditAwaitingUser) {
       $awaiting_user_phid = $this->auditAwaitingUser->getPHID();
       // Exclude package and project audits associated with commits where
       // the user is the author.
       $where[] = qsprintf(
         $conn_r,
         '(commit.authorPHID IS NULL OR commit.authorPHID != %s)
           OR (audit.auditorPHID = %s)',
         $awaiting_user_phid,
         $awaiting_user_phid);
     }
 
     $status = $this->auditStatus;
     if ($status !== null) {
       switch ($status) {
         case self::AUDIT_STATUS_PARTIAL:
           $where[] = qsprintf(
             $conn_r,
             'commit.auditStatus = %d',
             PhabricatorAuditCommitStatusConstants::PARTIALLY_AUDITED);
           break;
         case self::AUDIT_STATUS_ACCEPTED:
           $where[] = qsprintf(
             $conn_r,
             'commit.auditStatus = %d',
             PhabricatorAuditCommitStatusConstants::FULLY_AUDITED);
           break;
         case self::AUDIT_STATUS_CONCERN:
           $where[] = qsprintf(
             $conn_r,
             'audit.auditStatus = %s',
             PhabricatorAuditStatusConstants::CONCERNED);
           break;
         case self::AUDIT_STATUS_OPEN:
           $where[] = qsprintf(
             $conn_r,
             'audit.auditStatus in (%Ls)',
             PhabricatorAuditStatusConstants::getOpenStatusConstants());
           if ($this->auditAwaitingUser) {
             $where[] = qsprintf(
               $conn_r,
               'awaiting.auditStatus IS NULL OR awaiting.auditStatus != %s',
               PhabricatorAuditStatusConstants::RESIGNED);
           }
           break;
         case self::AUDIT_STATUS_ANY:
           break;
         default:
           $valid = array(
             self::AUDIT_STATUS_ANY,
             self::AUDIT_STATUS_OPEN,
             self::AUDIT_STATUS_CONCERN,
             self::AUDIT_STATUS_ACCEPTED,
             self::AUDIT_STATUS_PARTIAL,
           );
           throw new Exception(
             "Unknown audit status '{$status}'! Valid statuses are: ".
             implode(', ', $valid));
       }
     }
 
     $where[] = $this->buildPagingClause($conn_r);
 
     return $this->formatWhereClause($where);
   }
 
   protected function didFilterResults(array $filtered) {
     if ($this->identifierMap) {
       foreach ($this->identifierMap as $name => $commit) {
         if (isset($filtered[$commit->getPHID()])) {
           unset($this->identifierMap[$name]);
         }
       }
     }
   }
 
   private function buildJoinClause($conn_r) {
     $joins = array();
     $audit_request = new PhabricatorRepositoryAuditRequest();
 
     if ($this->shouldJoinAudits()) {
       $joins[] = qsprintf(
         $conn_r,
         '%Q %T audit ON commit.phid = audit.commitPHID',
         ($this->rowsMustHaveAudits() ? 'JOIN' : 'LEFT JOIN'),
         $audit_request->getTableName());
     }
 
     if ($this->auditAwaitingUser) {
       // Join the request table on the awaiting user's requests, so we can
       // filter out package and project requests which the user has resigned
       // from.
       $joins[] = qsprintf(
         $conn_r,
         'LEFT JOIN %T awaiting ON audit.commitPHID = awaiting.commitPHID AND
         awaiting.auditorPHID = %s',
         $audit_request->getTableName(),
         $this->auditAwaitingUser->getPHID());
     }
 
     if ($joins) {
       return implode(' ', $joins);
     } else {
       return '';
     }
   }
 
   private function buildGroupClause(AphrontDatabaseConnection $conn_r) {
     $should_group = $this->shouldJoinAudits();
 
     // TODO: Currently, the audit table is missing a unique key, so we may
     // require a GROUP BY if we perform this join. See T1768. This can be
     // removed once the table has the key.
     if ($this->auditAwaitingUser) {
       $should_group = true;
     }
 
     if ($should_group) {
       return 'GROUP BY commit.id';
     } else {
       return '';
     }
   }
 
   public function getQueryApplicationClass() {
     return 'PhabricatorDiffusionApplication';
   }
 
 }
diff --git a/src/applications/phrequent/query/PhrequentUserTimeQuery.php b/src/applications/phrequent/query/PhrequentUserTimeQuery.php
index 06a9028a13..ecf8656fe5 100644
--- a/src/applications/phrequent/query/PhrequentUserTimeQuery.php
+++ b/src/applications/phrequent/query/PhrequentUserTimeQuery.php
@@ -1,335 +1,337 @@
 <?php
 
 final class PhrequentUserTimeQuery
   extends PhabricatorCursorPagedPolicyAwareQuery {
 
   const ORDER_ID_ASC        = 0;
   const ORDER_ID_DESC       = 1;
   const ORDER_STARTED_ASC   = 2;
   const ORDER_STARTED_DESC  = 3;
   const ORDER_ENDED_ASC     = 4;
   const ORDER_ENDED_DESC    = 5;
-  const ORDER_DURATION_ASC  = 6;
-  const ORDER_DURATION_DESC = 7;
 
   const ENDED_YES = 0;
   const ENDED_NO  = 1;
   const ENDED_ALL = 2;
 
+  private $ids;
   private $userPHIDs;
   private $objectPHIDs;
-  private $order = self::ORDER_ID_ASC;
   private $ended = self::ENDED_ALL;
 
   private $needPreemptingEvents;
 
-  public function withUserPHIDs($user_phids) {
+  public function withIDs(array $ids) {
+    $this->ids = $ids;
+    return $this;
+  }
+
+  public function withUserPHIDs(array $user_phids) {
     $this->userPHIDs = $user_phids;
     return $this;
   }
 
-  public function withObjectPHIDs($object_phids) {
+  public function withObjectPHIDs(array $object_phids) {
     $this->objectPHIDs = $object_phids;
     return $this;
   }
 
   public function withEnded($ended) {
     $this->ended = $ended;
     return $this;
   }
 
   public function setOrder($order) {
-    $this->order = $order;
+    switch ($order) {
+      case self::ORDER_ID_ASC:
+        $this->setOrderVector(array('-id'));
+        break;
+      case self::ORDER_ID_DESC:
+        $this->setOrderVector(array('id'));
+        break;
+      case self::ORDER_STARTED_ASC:
+        $this->setOrderVector(array('-start', '-id'));
+        break;
+      case self::ORDER_STARTED_DESC:
+        $this->setOrderVector(array('start', 'id'));
+        break;
+      case self::ORDER_ENDED_ASC:
+        $this->setOrderVector(array('-ongoing', '-end', '-id'));
+        break;
+      case self::ORDER_ENDED_DESC:
+        $this->setOrderVector(array('ongoing', 'end', 'id'));
+        break;
+      default:
+        throw new Exception(pht('Unknown order "%s".', $order));
+    }
+
     return $this;
   }
 
   public function needPreemptingEvents($need_events) {
     $this->needPreemptingEvents = $need_events;
     return $this;
   }
 
   private function buildWhereClause(AphrontDatabaseConnection $conn) {
     $where = array();
 
-    if ($this->userPHIDs) {
+    if ($this->ids !== null) {
+      $where[] = qsprintf(
+        $conn,
+        'id IN (%Ld)',
+        $this->ids);
+    }
+
+    if ($this->userPHIDs !== null) {
       $where[] = qsprintf(
         $conn,
         'userPHID IN (%Ls)',
         $this->userPHIDs);
     }
 
-    if ($this->objectPHIDs) {
+    if ($this->objectPHIDs !== null) {
       $where[] = qsprintf(
         $conn,
         'objectPHID IN (%Ls)',
         $this->objectPHIDs);
     }
 
     switch ($this->ended) {
       case self::ENDED_ALL:
         break;
       case self::ENDED_YES:
         $where[] = qsprintf(
           $conn,
           'dateEnded IS NOT NULL');
         break;
       case self::ENDED_NO:
         $where[] = qsprintf(
           $conn,
           'dateEnded IS NULL');
         break;
       default:
         throw new Exception("Unknown ended '{$this->ended}'!");
     }
 
     $where[] = $this->buildPagingClause($conn);
 
     return $this->formatWhereClause($where);
   }
 
-  protected function getPagingColumn() {
-    switch ($this->order) {
-      case self::ORDER_ID_ASC:
-      case self::ORDER_ID_DESC:
-        return 'id';
-      case self::ORDER_STARTED_ASC:
-      case self::ORDER_STARTED_DESC:
-        return 'dateStarted';
-      case self::ORDER_ENDED_ASC:
-      case self::ORDER_ENDED_DESC:
-        return 'dateEnded';
-      case self::ORDER_DURATION_ASC:
-      case self::ORDER_DURATION_DESC:
-        return 'COALESCE(dateEnded, UNIX_TIMESTAMP()) - dateStarted';
-      default:
-        throw new Exception("Unknown order '{$this->order}'!");
-    }
-  }
-
-  protected function getPagingValue($result) {
-    switch ($this->order) {
-      case self::ORDER_ID_ASC:
-      case self::ORDER_ID_DESC:
-        return $result->getID();
-      case self::ORDER_STARTED_ASC:
-      case self::ORDER_STARTED_DESC:
-        return $result->getDateStarted();
-      case self::ORDER_ENDED_ASC:
-      case self::ORDER_ENDED_DESC:
-        return $result->getDateEnded();
-      case self::ORDER_DURATION_ASC:
-      case self::ORDER_DURATION_DESC:
-        return ($result->getDateEnded() || time()) - $result->getDateStarted();
-      default:
-        throw new Exception("Unknown order '{$this->order}'!");
-    }
+  public function getOrderableColumns() {
+    return parent::getOrderableColumns() + array(
+      'start' => array(
+        'column' => 'dateStarted',
+        'type' => 'int',
+      ),
+      'ongoing' => array(
+        'column' => 'dateEnded',
+        'type' => 'null',
+      ),
+      'end' => array(
+        'column' => 'dateEnded',
+        'type' => 'int',
+      ),
+    );
   }
 
-  protected function getReversePaging() {
-    switch ($this->order) {
-      case self::ORDER_ID_ASC:
-      case self::ORDER_STARTED_ASC:
-      case self::ORDER_ENDED_ASC:
-      case self::ORDER_DURATION_ASC:
-        return true;
-      case self::ORDER_ID_DESC:
-      case self::ORDER_STARTED_DESC:
-      case self::ORDER_ENDED_DESC:
-      case self::ORDER_DURATION_DESC:
-        return false;
-      default:
-        throw new Exception("Unknown order '{$this->order}'!");
-    }
+  protected function getPagingValueMap($cursor, array $keys) {
+    $usertime = $this->loadCursorObject($cursor);
+    return array(
+      'id' => $usertime->getID(),
+      'start' => $usertime->getDateStarted(),
+      'ongoing' => $usertime->getDateEnded(),
+      'end' => $usertime->getDateEnded(),
+    );
   }
 
   protected function loadPage() {
     $usertime = new PhrequentUserTime();
     $conn = $usertime->establishConnection('r');
 
     $data = queryfx_all(
       $conn,
       'SELECT usertime.* FROM %T usertime %Q %Q %Q',
       $usertime->getTableName(),
       $this->buildWhereClause($conn),
       $this->buildOrderClause($conn),
       $this->buildLimitClause($conn));
 
     return $usertime->loadAllFromArray($data);
   }
 
   protected function didFilterPage(array $page) {
     if ($this->needPreemptingEvents) {
       $usertime = new PhrequentUserTime();
       $conn_r = $usertime->establishConnection('r');
 
       $preempt = array();
       foreach ($page as $event) {
         $preempt[] = qsprintf(
           $conn_r,
           '(userPHID = %s AND
             (dateStarted BETWEEN %d AND %d) AND
             (dateEnded IS NULL OR dateEnded > %d))',
           $event->getUserPHID(),
           $event->getDateStarted(),
           nonempty($event->getDateEnded(), PhabricatorTime::getNow()),
           $event->getDateStarted());
       }
 
       $preempting_events = queryfx_all(
         $conn_r,
         'SELECT * FROM %T WHERE %Q ORDER BY dateStarted ASC, id ASC',
         $usertime->getTableName(),
         implode(' OR ', $preempt));
       $preempting_events = $usertime->loadAllFromArray($preempting_events);
 
       $preempting_events = mgroup($preempting_events, 'getUserPHID');
 
       foreach ($page as $event) {
         $e_start = $event->getDateStarted();
         $e_end = $event->getDateEnded();
 
         $select = array();
         $user_events = idx($preempting_events, $event->getUserPHID(), array());
         foreach ($user_events as $u_event) {
           if ($u_event->getID() == $event->getID()) {
             // Don't allow an event to preempt itself.
             continue;
           }
 
           $u_start = $u_event->getDateStarted();
           $u_end = $u_event->getDateEnded();
 
           if ($u_start < $e_start) {
             // This event started before our event started, so it's not
             // preempting us.
             continue;
           }
 
           if ($u_start == $e_start) {
             if ($u_event->getID() < $event->getID()) {
               // This event started at the same time as our event started,
               // but has a lower ID, so it's not preempting us.
               continue;
             }
           }
 
           if (($e_end !== null) && ($u_start > $e_end)) {
             // Our event has ended, and this event started after it ended.
             continue;
           }
 
           if (($u_end !== null) && ($u_end < $e_start)) {
             // This event ended before our event began.
             continue;
           }
 
           $select[] = $u_event;
         }
 
         $event->attachPreemptingEvents($select);
       }
     }
 
     return $page;
   }
 
 /* -(  Helper Functions ) --------------------------------------------------- */
 
   public static function getEndedSearchOptions() {
     return array(
       self::ENDED_ALL => pht('All'),
       self::ENDED_NO  => pht('No'),
       self::ENDED_YES => pht('Yes'),
     );
   }
 
   public static function getOrderSearchOptions() {
     return array(
       self::ORDER_STARTED_ASC   => pht('by furthest start date'),
       self::ORDER_STARTED_DESC  => pht('by nearest start date'),
       self::ORDER_ENDED_ASC     => pht('by furthest end date'),
       self::ORDER_ENDED_DESC    => pht('by nearest end date'),
-      self::ORDER_DURATION_ASC  => pht('by smallest duration'),
-      self::ORDER_DURATION_DESC => pht('by largest duration'),
     );
   }
 
   public static function getUserTotalObjectsTracked(
     PhabricatorUser $user,
     $limit = PHP_INT_MAX) {
 
     $usertime_dao = new PhrequentUserTime();
     $conn = $usertime_dao->establishConnection('r');
 
     $count = queryfx_one(
       $conn,
       'SELECT COUNT(usertime.id) N FROM %T usertime '.
       'WHERE usertime.userPHID = %s '.
       'AND usertime.dateEnded IS NULL '.
       'LIMIT %d',
       $usertime_dao->getTableName(),
       $user->getPHID(),
       $limit);
     return $count['N'];
   }
 
   public static function isUserTrackingObject(
     PhabricatorUser $user,
     $phid) {
 
     $usertime_dao = new PhrequentUserTime();
     $conn = $usertime_dao->establishConnection('r');
 
     $count = queryfx_one(
       $conn,
       'SELECT COUNT(usertime.id) N FROM %T usertime '.
       'WHERE usertime.userPHID = %s '.
       'AND usertime.objectPHID = %s '.
       'AND usertime.dateEnded IS NULL',
       $usertime_dao->getTableName(),
       $user->getPHID(),
       $phid);
     return $count['N'] > 0;
   }
 
   public static function getUserTimeSpentOnObject(
     PhabricatorUser $user,
     $phid) {
 
     $usertime_dao = new PhrequentUserTime();
     $conn = $usertime_dao->establishConnection('r');
 
     // First calculate all the time spent where the
     // usertime blocks have ended.
     $sum_ended = queryfx_one(
       $conn,
       'SELECT SUM(usertime.dateEnded - usertime.dateStarted) N '.
       'FROM %T usertime '.
       'WHERE usertime.userPHID = %s '.
       'AND usertime.objectPHID = %s '.
       'AND usertime.dateEnded IS NOT NULL',
       $usertime_dao->getTableName(),
       $user->getPHID(),
       $phid);
 
     // Now calculate the time spent where the usertime
     // blocks have not yet ended.
     $sum_not_ended = queryfx_one(
       $conn,
       'SELECT SUM(UNIX_TIMESTAMP() - usertime.dateStarted) N '.
       'FROM %T usertime '.
       'WHERE usertime.userPHID = %s '.
       'AND usertime.objectPHID = %s '.
       'AND usertime.dateEnded IS NULL',
       $usertime_dao->getTableName(),
       $user->getPHID(),
       $phid);
 
     return $sum_ended['N'] + $sum_not_ended['N'];
   }
 
   public function getQueryApplicationClass() {
     return 'PhabricatorPhrequentApplication';
   }
 
 }
diff --git a/src/infrastructure/query/policy/PhabricatorCursorPagedPolicyAwareQuery.php b/src/infrastructure/query/policy/PhabricatorCursorPagedPolicyAwareQuery.php
index fdeb3cd459..dceaf6c331 100644
--- a/src/infrastructure/query/policy/PhabricatorCursorPagedPolicyAwareQuery.php
+++ b/src/infrastructure/query/policy/PhabricatorCursorPagedPolicyAwareQuery.php
@@ -1,948 +1,950 @@
 <?php
 
 /**
  * A query class which uses cursor-based paging. This paging is much more
  * performant than offset-based paging in the presence of policy filtering.
  *
  * @task appsearch Integration with ApplicationSearch
  * @task paging Paging
  * @task order Result Ordering
  */
 abstract class PhabricatorCursorPagedPolicyAwareQuery
   extends PhabricatorPolicyAwareQuery {
 
   private $afterID;
   private $beforeID;
   private $applicationSearchConstraints = array();
   private $applicationSearchOrders = array();
   private $internalPaging;
   private $orderVector;
 
   protected function getPagingColumn() {
     return 'id';
   }
 
   protected function getPagingValue($result) {
     if (!is_object($result)) {
       // This interface can't be typehinted and PHP gets really angry if we
       // call a method on a non-object, so add an explicit check here.
       throw new Exception(pht('Expected object, got "%s"!', gettype($result)));
     }
     return $result->getID();
   }
 
   protected function getReversePaging() {
     return false;
   }
 
   protected function nextPage(array $page) {
     // See getPagingViewer() for a description of this flag.
     $this->internalPaging = true;
 
     if ($this->beforeID) {
       $this->beforeID = $this->getPagingValue(last($page));
     } else {
       $this->afterID = $this->getPagingValue(last($page));
     }
   }
 
   final public function setAfterID($object_id) {
     $this->afterID = $object_id;
     return $this;
   }
 
   final protected function getAfterID() {
     return $this->afterID;
   }
 
   final public function setBeforeID($object_id) {
     $this->beforeID = $object_id;
     return $this;
   }
 
   final protected function getBeforeID() {
     return $this->beforeID;
   }
 
 
   /**
    * Get the viewer for making cursor paging queries.
    *
    * NOTE: You should ONLY use this viewer to load cursor objects while
    * building paging queries.
    *
    * Cursor paging can happen in two ways. First, the user can request a page
    * like `/stuff/?after=33`, which explicitly causes paging. Otherwise, we
    * can fall back to implicit paging if we filter some results out of a
    * result list because the user can't see them and need to go fetch some more
    * results to generate a large enough result list.
    *
    * In the first case, want to use the viewer's policies to load the object.
    * This prevents an attacker from figuring out information about an object
    * they can't see by executing queries like `/stuff/?after=33&order=name`,
    * which would otherwise give them a hint about the name of the object.
    * Generally, if a user can't see an object, they can't use it to page.
    *
    * In the second case, we need to load the object whether the user can see
    * it or not, because we need to examine new results. For example, if a user
    * loads `/stuff/` and we run a query for the first 100 items that they can
    * see, but the first 100 rows in the database aren't visible, we need to
    * be able to issue a query for the next 100 results. If we can't load the
    * cursor object, we'll fail or issue the same query over and over again.
    * So, generally, internal paging must bypass policy controls.
    *
    * This method returns the appropriate viewer, based on the context in which
    * the paging is occuring.
    *
    * @return PhabricatorUser Viewer for executing paging queries.
    */
   final protected function getPagingViewer() {
     if ($this->internalPaging) {
       return PhabricatorUser::getOmnipotentUser();
     } else {
       return $this->getViewer();
     }
   }
 
   final protected function buildLimitClause(AphrontDatabaseConnection $conn_r) {
     if ($this->getRawResultLimit()) {
       return qsprintf($conn_r, 'LIMIT %d', $this->getRawResultLimit());
     } else {
       return '';
     }
   }
 
   final protected function didLoadResults(array $results) {
     if ($this->beforeID) {
       $results = array_reverse($results, $preserve_keys = true);
     }
     return $results;
   }
 
   final public function executeWithCursorPager(AphrontCursorPagerView $pager) {
     $this->setLimit($pager->getPageSize() + 1);
 
     if ($pager->getAfterID()) {
       $this->setAfterID($pager->getAfterID());
     } else if ($pager->getBeforeID()) {
       $this->setBeforeID($pager->getBeforeID());
     }
 
     $results = $this->execute();
 
     $sliced_results = $pager->sliceResults($results);
 
     if ($sliced_results) {
       if ($pager->getBeforeID() || (count($results) > $pager->getPageSize())) {
         $pager->setNextPageID($this->getPagingValue(last($sliced_results)));
       }
 
       if ($pager->getAfterID() ||
          ($pager->getBeforeID() && (count($results) > $pager->getPageSize()))) {
         $pager->setPrevPageID($this->getPagingValue(head($sliced_results)));
       }
     }
 
     return $sliced_results;
   }
 
 
   /**
    * Return the alias this query uses to identify the primary table.
    *
    * Some automatic query constructions may need to be qualified with a table
    * alias if the query performs joins which make column names ambiguous. If
    * this is the case, return the alias for the primary table the query
    * uses; generally the object table which has `id` and `phid` columns.
    *
    * @return string Alias for the primary table.
    */
   protected function getPrimaryTableAlias() {
     return null;
   }
 
 
 /* -(  Paging  )------------------------------------------------------------- */
 
 
   protected function buildPagingClause(AphrontDatabaseConnection $conn) {
     $orderable = $this->getOrderableColumns();
 
     // TODO: Remove this once subqueries modernize.
     if (!$orderable) {
       if ($this->beforeID) {
         return qsprintf(
           $conn,
           '%Q %Q %s',
           $this->getPagingColumn(),
           $this->getReversePaging() ? '<' : '>',
           $this->beforeID);
       } else if ($this->afterID) {
         return qsprintf(
           $conn,
           '%Q %Q %s',
           $this->getPagingColumn(),
           $this->getReversePaging() ? '>' : '<',
           $this->afterID);
       } else {
         return null;
       }
     }
 
     $vector = $this->getOrderVector();
 
     if ($this->beforeID !== null) {
       $cursor = $this->beforeID;
       $reversed = true;
     } else if ($this->afterID !== null) {
       $cursor = $this->afterID;
       $reversed = false;
     } else {
       // No paging is being applied to this query so we do not need to
       // construct a paging clause.
       return '';
     }
 
     $keys = array();
     foreach ($vector as $order) {
       $keys[] = $order->getOrderKey();
     }
 
     $value_map = $this->getPagingValueMap($cursor, $keys);
 
     $columns = array();
     foreach ($vector as $order) {
       $key = $order->getOrderKey();
 
       if (!array_key_exists($key, $value_map)) {
         throw new Exception(
           pht(
             'Query "%s" failed to return a value from getPagingValueMap() '.
             'for column "%s".',
             get_class($this),
             $key));
       }
 
       $column = $orderable[$key];
       $column['value'] = $value_map[$key];
 
       $columns[] = $column;
     }
 
     return $this->buildPagingClauseFromMultipleColumns(
       $conn,
       $columns,
       array(
         'reversed' => $reversed,
       ));
   }
 
   protected function getPagingValueMap($cursor, array $keys) {
     // TODO: This is a hack to make this work with existing classes for now.
     return array(
       'id' => $cursor,
     );
   }
 
   protected function loadCursorObject($cursor) {
     $query = newv(get_class($this), array())
       ->setViewer($this->getPagingViewer())
       ->withIDs(array((int)$cursor));
 
     $this->willExecuteCursorQuery($query);
 
     $object = $query->executeOne();
     if (!$object) {
       throw new Exception(
         pht(
           'Cursor "%s" does not identify a valid object.',
           $cursor));
     }
 
     return $object;
   }
 
   protected function willExecuteCursorQuery(
     PhabricatorCursorPagedPolicyAwareQuery $query) {
     return;
   }
 
 
   /**
    * Simplifies the task of constructing a paging clause across multiple
    * columns. In the general case, this looks like:
    *
    *   A > a OR (A = a AND B > b) OR (A = a AND B = b AND C > c)
    *
    * To build a clause, specify the name, type, and value of each column
    * to include:
    *
    *   $this->buildPagingClauseFromMultipleColumns(
    *     $conn_r,
    *     array(
    *       array(
    *         'table' => 't',
    *         'column' => 'title',
    *         'type' => 'string',
    *         'value' => $cursor->getTitle(),
    *         'reverse' => true,
    *       ),
    *       array(
    *         'table' => 't',
    *         'column' => 'id',
    *         'type' => 'int',
    *         'value' => $cursor->getID(),
    *       ),
    *     ),
    *     array(
    *       'reversed' => $is_reversed,
    *     ));
    *
    * This method will then return a composable clause for inclusion in WHERE.
    *
    * @param AphrontDatabaseConnection Connection query will execute on.
    * @param list<map> Column description dictionaries.
    * @param map Additional constuction options.
    * @return string Query clause.
    */
   final protected function buildPagingClauseFromMultipleColumns(
     AphrontDatabaseConnection $conn,
     array $columns,
     array $options) {
 
     foreach ($columns as $column) {
       PhutilTypeSpec::checkMap(
         $column,
         array(
           'table' => 'optional string|null',
           'column' => 'string',
           'value' => 'wild',
           'type' => 'string',
           'reverse' => 'optional bool',
           'unique' => 'optional bool',
         ));
     }
 
     PhutilTypeSpec::checkMap(
       $options,
       array(
         'reversed' => 'optional bool',
       ));
 
     $is_query_reversed = idx($options, 'reversed', false);
 
     $clauses = array();
     $accumulated = array();
     $last_key = last_key($columns);
     foreach ($columns as $key => $column) {
       $type = $column['type'];
       switch ($type) {
         case 'null':
           $value = qsprintf($conn, '%d', ($column['value'] ? 0 : 1));
           break;
         case 'int':
           $value = qsprintf($conn, '%d', $column['value']);
           break;
         case 'float':
           $value = qsprintf($conn, '%f', $column['value']);
           break;
         case 'string':
           $value = qsprintf($conn, '%s', $column['value']);
           break;
         default:
           throw new Exception("Unknown column type '{$type}'!");
       }
 
       $is_column_reversed = idx($column, 'reverse', false);
       $reverse = ($is_query_reversed xor $is_column_reversed);
 
       $clause = $accumulated;
 
       $table_name = idx($column, 'table');
       $column_name = $column['column'];
       if ($table_name !== null) {
         $field = qsprintf($conn, '%T.%T', $table_name, $column_name);
       } else {
         $field = qsprintf($conn, '%T', $column_name);
       }
 
       if ($type == 'null') {
         $field = qsprintf($conn, '(%Q IS NULL)', $field);
       }
 
       $clause[] = qsprintf(
         $conn,
         '%Q %Q %Q',
         $field,
         $reverse ? '>' : '<',
         $value);
       $clauses[] = '('.implode(') AND (', $clause).')';
 
       $accumulated[] = qsprintf(
         $conn,
         '%Q = %Q',
         $field,
         $value);
     }
 
     return '('.implode(') OR (', $clauses).')';
   }
 
 
 /* -(  Result Ordering  )---------------------------------------------------- */
 
 
   /**
    * @task order
    */
   public function setOrderVector($vector) {
     $vector = PhabricatorQueryOrderVector::newFromVector($vector);
 
     $orderable = $this->getOrderableColumns();
 
     // Make sure that all the components identify valid columns.
     $unique = array();
     foreach ($vector as $order) {
       $key = $order->getOrderKey();
       if (empty($orderable[$key])) {
         $valid = implode(', ', array_keys($orderable));
         throw new Exception(
           pht(
             'This query ("%s") does not support sorting by order key "%s". '.
             'Supported orders are: %s.',
             get_class($this),
             $key,
             $valid));
       }
 
       $unique[$key] = idx($orderable[$key], 'unique', false);
     }
 
     // Make sure that the last column is unique so that this is a strong
     // ordering which can be used for paging.
     $last = last($unique);
     if ($last !== true) {
       throw new Exception(
         pht(
           'Order vector "%s" is invalid: the last column in an order must '.
           'be a column with unique values, but "%s" is not unique.',
           $vector->getAsString(),
           last_key($unique)));
     }
 
     // Make sure that other columns are not unique; an ordering like "id, name"
     // does not make sense because only "id" can ever have an effect.
     array_pop($unique);
     foreach ($unique as $key => $is_unique) {
       if ($is_unique) {
         throw new Exception(
           pht(
             'Order vector "%s" is invalid: only the last column in an order '.
             'may be unique, but "%s" is a unique column and not the last '.
             'column in the order.',
             $vector->getAsString(),
             $key));
       }
     }
 
     $this->orderVector = $vector;
     return $this;
   }
 
 
   /**
    * @task order
    */
   protected function getOrderVector() {
     if (!$this->orderVector) {
       $vector = $this->getDefaultOrderVector();
       $vector = PhabricatorQueryOrderVector::newFromVector($vector);
 
       // We call setOrderVector() here to apply checks to the default vector.
       // This catches any errors in the implementation.
       $this->setOrderVector($vector);
     }
 
     return $this->orderVector;
   }
 
 
   /**
    * @task order
    */
   protected function getDefaultOrderVector() {
     return array('id');
   }
 
 
   /**
    * @task order
    */
   public function getOrderableColumns() {
     // TODO: Remove this once all subclasses move off the old stuff.
     if ($this->getPagingColumn() !== 'id') {
       // This class has bad old custom logic around paging, so return nothing
       // here. This deactivates the new order code.
       return array();
     }
 
     return array(
       'id' => array(
         'table' => $this->getPrimaryTableAlias(),
         'column' => 'id',
         'reverse' => false,
         'type' => 'int',
         'unique' => true,
       ),
     );
   }
 
 
   /**
    * @task order
    */
   final protected function buildOrderClause(AphrontDatabaseConnection $conn) {
     $orderable = $this->getOrderableColumns();
 
     // TODO: Remove this once all subclasses move off the old stuff. We'll
     // only enter this block for code using older ordering mechanisms. New
     // code should expose an orderable column list.
     if (!$orderable) {
       if ($this->beforeID) {
         return qsprintf(
           $conn,
           'ORDER BY %Q %Q',
           $this->getPagingColumn(),
           $this->getReversePaging() ? 'DESC' : 'ASC');
       } else {
         return qsprintf(
           $conn,
           'ORDER BY %Q %Q',
           $this->getPagingColumn(),
           $this->getReversePaging() ? 'ASC' : 'DESC');
       }
     }
 
     $vector = $this->getOrderVector();
 
     $parts = array();
     foreach ($vector as $order) {
       $part = $orderable[$order->getOrderKey()];
       if ($order->getIsReversed()) {
         $part['reverse'] = !idx($part, 'reverse', false);
       }
       $parts[] = $part;
     }
 
     return $this->formatOrderClause($conn, $parts);
   }
 
 
   /**
    * @task order
    */
   protected function formatOrderClause(
     AphrontDatabaseConnection $conn,
     array $parts) {
 
     $is_query_reversed = false;
     if ($this->getReversePaging()) {
       $is_query_reversed = !$is_query_reversed;
     }
 
     if ($this->getBeforeID()) {
       $is_query_reversed = !$is_query_reversed;
     }
 
     $sql = array();
     foreach ($parts as $key => $part) {
       $is_column_reversed = !empty($part['reverse']);
 
       $descending = true;
       if ($is_query_reversed) {
         $descending = !$descending;
       }
 
       if ($is_column_reversed) {
         $descending = !$descending;
       }
 
       $table = idx($part, 'table');
       $column = $part['column'];
 
+      if ($table !== null) {
+        $field = qsprintf($conn, '%T.%T', $table, $column);
+      } else {
+        $field = qsprintf($conn, '%T', $column);
+      }
+
+      if (idx($part, 'type') === 'null') {
+        $field = qsprintf($conn, '(%Q IS NULL)', $field);
+      }
+
       if ($descending) {
-        if ($table !== null) {
-          $sql[] = qsprintf($conn, '%T.%T DESC', $table, $column);
-        } else {
-          $sql[] = qsprintf($conn, '%T DESC', $column);
-        }
+        $sql[] = qsprintf($conn, '%Q DESC', $field);
       } else {
-        if ($table !== null) {
-          $sql[] = qsprintf($conn, '%T.%T ASC', $table, $column);
-        } else {
-          $sql[] = qsprintf($conn, '%T ASC', $column);
-        }
+        $sql[] = qsprintf($conn, '%Q ASC', $field);
       }
     }
 
     return qsprintf($conn, 'ORDER BY %Q', implode(', ', $sql));
   }
 
 
 /* -(  Application Search  )------------------------------------------------- */
 
 
   /**
    * Constrain the query with an ApplicationSearch index, requiring field values
    * contain at least one of the values in a set.
    *
    * This constraint can build the most common types of queries, like:
    *
    *   - Find users with shirt sizes "X" or "XL".
    *   - Find shoes with size "13".
    *
    * @param PhabricatorCustomFieldIndexStorage Table where the index is stored.
    * @param string|list<string> One or more values to filter by.
    * @return this
    * @task appsearch
    */
   public function withApplicationSearchContainsConstraint(
     PhabricatorCustomFieldIndexStorage $index,
     $value) {
 
     $this->applicationSearchConstraints[] = array(
       'type'  => $index->getIndexValueType(),
       'cond'  => '=',
       'table' => $index->getTableName(),
       'index' => $index->getIndexKey(),
       'value' => $value,
     );
 
     return $this;
   }
 
 
   /**
    * Constrain the query with an ApplicationSearch index, requiring values
    * exist in a given range.
    *
    * This constraint is useful for expressing date ranges:
    *
    *   - Find events between July 1st and July 7th.
    *
    * The ends of the range are inclusive, so a `$min` of `3` and a `$max` of
    * `5` will match fields with values `3`, `4`, or `5`. Providing `null` for
    * either end of the range will leave that end of the constraint open.
    *
    * @param PhabricatorCustomFieldIndexStorage Table where the index is stored.
    * @param int|null Minimum permissible value, inclusive.
    * @param int|null Maximum permissible value, inclusive.
    * @return this
    * @task appsearch
    */
   public function withApplicationSearchRangeConstraint(
     PhabricatorCustomFieldIndexStorage $index,
     $min,
     $max) {
 
     $index_type = $index->getIndexValueType();
     if ($index_type != 'int') {
       throw new Exception(
         pht(
           'Attempting to apply a range constraint to a field with index type '.
           '"%s", expected type "%s".',
           $index_type,
           'int'));
     }
 
     $this->applicationSearchConstraints[] = array(
       'type' => $index->getIndexValueType(),
       'cond' => 'range',
       'table' => $index->getTableName(),
       'index' => $index->getIndexKey(),
       'value' => array($min, $max),
     );
 
     return $this;
   }
 
 
   /**
    * Order the results by an ApplicationSearch index.
    *
    * @param PhabricatorCustomField Field to which the index belongs.
    * @param PhabricatorCustomFieldIndexStorage Table where the index is stored.
    * @param bool True to sort ascending.
    * @return this
    * @task appsearch
    */
   public function withApplicationSearchOrder(
     PhabricatorCustomField $field,
     PhabricatorCustomFieldIndexStorage $index,
     $ascending) {
 
     $this->applicationSearchOrders[] = array(
       'key' => $field->getFieldKey(),
       'type' => $index->getIndexValueType(),
       'table' => $index->getTableName(),
       'index' => $index->getIndexKey(),
       'ascending' => $ascending,
     );
 
     return $this;
   }
 
 
   /**
    * Get the name of the query's primary object PHID column, for constructing
    * JOIN clauses. Normally (and by default) this is just `"phid"`, but it may
    * be something more exotic.
    *
    * See @{method:getPrimaryTableAlias} if the column needs to be qualified with
    * a table alias.
    *
    * @return string Column name.
    * @task appsearch
    */
   protected function getApplicationSearchObjectPHIDColumn() {
     if ($this->getPrimaryTableAlias()) {
       $prefix = $this->getPrimaryTableAlias().'.';
     } else {
       $prefix = '';
     }
 
     return $prefix.'phid';
   }
 
 
   /**
    * Determine if the JOINs built by ApplicationSearch might cause each primary
    * object to return multiple result rows. Generally, this means the query
    * needs an extra GROUP BY clause.
    *
    * @return bool True if the query may return multiple rows for each object.
    * @task appsearch
    */
   protected function getApplicationSearchMayJoinMultipleRows() {
     foreach ($this->applicationSearchConstraints as $constraint) {
       $type = $constraint['type'];
       $value = $constraint['value'];
       $cond = $constraint['cond'];
 
       switch ($cond) {
         case '=':
           switch ($type) {
             case 'string':
             case 'int':
               if (count((array)$value) > 1) {
                 return true;
               }
               break;
             default:
               throw new Exception(pht('Unknown index type "%s"!', $type));
           }
           break;
         case 'range':
           // NOTE: It's possible to write a custom field where multiple rows
           // match a range constraint, but we don't currently ship any in the
           // upstream and I can't immediately come up with cases where this
           // would make sense.
           break;
         default:
           throw new Exception(pht('Unknown constraint condition "%s"!', $cond));
       }
     }
 
     return false;
   }
 
 
   /**
    * Construct a GROUP BY clause appropriate for ApplicationSearch constraints.
    *
    * @param AphrontDatabaseConnection Connection executing the query.
    * @return string Group clause.
    * @task appsearch
    */
   protected function buildApplicationSearchGroupClause(
     AphrontDatabaseConnection $conn_r) {
 
     if ($this->getApplicationSearchMayJoinMultipleRows()) {
       return qsprintf(
         $conn_r,
         'GROUP BY %Q',
         $this->getApplicationSearchObjectPHIDColumn());
     } else {
       return '';
     }
   }
 
 
   /**
    * Construct a JOIN clause appropriate for applying ApplicationSearch
    * constraints.
    *
    * @param AphrontDatabaseConnection Connection executing the query.
    * @return string Join clause.
    * @task appsearch
    */
   protected function buildApplicationSearchJoinClause(
     AphrontDatabaseConnection $conn_r) {
 
     $joins = array();
     foreach ($this->applicationSearchConstraints as $key => $constraint) {
       $table = $constraint['table'];
       $alias = 'appsearch_'.$key;
       $index = $constraint['index'];
       $cond = $constraint['cond'];
       $phid_column = $this->getApplicationSearchObjectPHIDColumn();
       switch ($cond) {
         case '=':
           $type = $constraint['type'];
           switch ($type) {
             case 'string':
               $constraint_clause = qsprintf(
                 $conn_r,
                 '%T.indexValue IN (%Ls)',
                 $alias,
                 (array)$constraint['value']);
               break;
             case 'int':
               $constraint_clause = qsprintf(
                 $conn_r,
                 '%T.indexValue IN (%Ld)',
                 $alias,
                 (array)$constraint['value']);
               break;
             default:
               throw new Exception(pht('Unknown index type "%s"!', $type));
           }
 
           $joins[] = qsprintf(
             $conn_r,
             'JOIN %T %T ON %T.objectPHID = %Q
               AND %T.indexKey = %s
               AND (%Q)',
             $table,
             $alias,
             $alias,
             $phid_column,
             $alias,
             $index,
             $constraint_clause);
           break;
         case 'range':
           list($min, $max) = $constraint['value'];
           if (($min === null) && ($max === null)) {
             // If there's no actual range constraint, just move on.
             break;
           }
 
           if ($min === null) {
             $constraint_clause = qsprintf(
               $conn_r,
               '%T.indexValue <= %d',
               $alias,
               $max);
           } else if ($max === null) {
             $constraint_clause = qsprintf(
               $conn_r,
               '%T.indexValue >= %d',
               $alias,
               $min);
           } else {
             $constraint_clause = qsprintf(
               $conn_r,
               '%T.indexValue BETWEEN %d AND %d',
               $alias,
               $min,
               $max);
           }
 
           $joins[] = qsprintf(
             $conn_r,
             'JOIN %T %T ON %T.objectPHID = %Q
               AND %T.indexKey = %s
               AND (%Q)',
             $table,
             $alias,
             $alias,
             $phid_column,
             $alias,
             $index,
             $constraint_clause);
           break;
         default:
           throw new Exception(pht('Unknown constraint condition "%s"!', $cond));
       }
     }
 
     foreach ($this->applicationSearchOrders as $key => $order) {
       $table = $order['table'];
       $alias = 'appsearch_order_'.$key;
       $index = $order['index'];
       $phid_column = $this->getApplicationSearchObjectPHIDColumn();
 
       $joins[] = qsprintf(
         $conn_r,
         'LEFT JOIN %T %T ON %T.objectPHID = %Q
           AND %T.indexKey = %s',
         $table,
         $alias,
         $alias,
         $phid_column,
         $alias,
         $index);
     }
 
     return implode(' ', $joins);
   }
 
   protected function buildApplicationSearchOrders(
     AphrontDatabaseConnection $conn_r,
     $reverse) {
 
     $orders = array();
     foreach ($this->applicationSearchOrders as $key => $order) {
       $alias = 'appsearch_order_'.$key;
 
       if ($order['ascending'] xor $reverse) {
         $orders[] = qsprintf($conn_r, '%T.indexValue ASC', $alias);
       } else {
         $orders[] = qsprintf($conn_r, '%T.indexValue DESC', $alias);
       }
     }
 
     return $orders;
   }
 
   protected function buildApplicationSearchPagination(
     AphrontDatabaseConnection $conn_r,
     $cursor) {
 
     // We have to get the current field values on the cursor object.
     $fields = PhabricatorCustomField::getObjectFields(
       $cursor,
       PhabricatorCustomField::ROLE_APPLICATIONSEARCH);
     $fields->setViewer($this->getViewer());
     $fields->readFieldsFromStorage($cursor);
 
     $fields = mpull($fields->getFields(), null, 'getFieldKey');
 
     $columns = array();
     foreach ($this->applicationSearchOrders as $key => $order) {
       $alias = 'appsearch_order_'.$key;
 
       $field = idx($fields, $order['key']);
 
       $columns[] = array(
         'name' => $alias.'.indexValue',
         'value' => $field->getValueForStorage(),
         'type' => $order['type'],
       );
     }
 
     return $columns;
   }
 
 }