Issue #596: SQL change with some performance / resource improvements

classes/local/report/location_report_builder.php

@@ -50,31 +50,52 @@ public function build_report($reportid) {
  $filedircount = 0;
  $filedirsum = 0;
  foreach ($locations as $location) {
- $localsql = '';
+ $sql =
+ 'WITH
+ cte_objects AS (
+ SELECT o.contenthash, o.location
+ FROM {tool_objectfs_objects} o
+ WHERE o.location = ? ),
+ cte_obj_files AS (
+ SELECT f.contenthash, MAX(f.filesize) AS filesize
+ FROM {files} f
+ INNER JOIN cte_objects co ON f.contenthash = co.contenthash
+ WHERE filesize > 0
+ GROUP BY f.contenthash, f.filesize)
+ SELECT COALESCE(COUNT(cof.contenthash),0) AS objectcount,
+ COALESCE(SUM(cof.filesize),0) AS objectsum
+ FROM cte_obj_files cof';
+
  if ($location == OBJECT_LOCATION_LOCAL) {
- $localsql = ' or o.location IS NULL';
+ $sql =
+ 'WITH
+ cte_objects AS (
+ SELECT o.contenthash, o.location
+ FROM {tool_objectfs_objects} o ),
+ cte_obj_files AS (
+ SELECT f.contenthash, MAX(f.filesize) AS filesize
+ FROM {files} f
+ LEFT JOIN cte_objects co ON f.contenthash = co.contenthash
+ WHERE filesize > 0 AND ( co.location = ? OR co.location IS NULL )
+ GROUP BY f.contenthash, f.filesize)
+ SELECT COALESCE(COUNT(cof.contenthash),0) AS objectcount,
+ COALESCE(SUM(cof.filesize),0) AS objectsum
+ FROM cte_obj_files cof';
  }
 
- $sql = 'SELECT COALESCE(count(sub.contenthash) ,0) AS objectcount,
- COALESCE(SUM(sub.filesize) ,0) AS objectsum
- FROM (SELECT f.contenthash, MAX(f.filesize) AS filesize
- FROM {files} f
- LEFT JOIN {tool_objectfs_objects} o on f.contenthash = o.contenthash
- GROUP BY f.contenthash, f.filesize, o.location
- HAVING o.location = ?' . $localsql .') AS sub
- WHERE sub.filesize > 0';
-
  if ($location !== OBJECT_LOCATION_ORPHANED) {
  // Process the query normally.
  $result = $DB->get_record_sql($sql, array($location));
  } else if ($location === OBJECT_LOCATION_ORPHANED) {
  // Start the query from objectfs, for ORPHANED objects, they are not located in the files table.
- $sql = 'SELECT COALESCE(count(sub.contenthash) ,0) AS objectcount
- FROM (SELECT o.contenthash
- FROM {tool_objectfs_objects} o
- LEFT JOIN {files} f on f.contenthash = o.contenthash
- GROUP BY o.contenthash, f.filesize, o.location
- HAVING o.location = ?' . $localsql .') AS sub';
+ $sql =
+ 'WITH
+ cte_objects AS (
+ SELECT o.contenthash
+ FROM {tool_objectfs_objects} o
+ WHERE o.location = ?)
+ SELECT COALESCE(COUNT(co.contenthash),0) AS objectcount
+ FROM cte_objects co';
  $result = $DB->get_record_sql($sql, array($location));
  $result->objectsum = 0;
  }