purge_orphans: optimize the query, maybe

https://tt-rss.org/forum/viewtopic.php?f=1&t=3417&p=20408#p20407

diff --git a/include/functions.php b/include/functions.php
index 22179e1a4c74f59598fba6b753bef8573cc2ad7d..e5f2ca48667888bfec253690c651d70c4a74a0c9 100644 (file)
--- a/include/functions.php
+++ b/include/functions.php
@@ -320,7 +320,7 @@
 
                // purge orphaned posts in main content table
                $result = db_query("DELETE FROM ttrss_entries WHERE
-                       (SELECT COUNT(int_id) FROM ttrss_user_entries WHERE ref_id = id) = 0");
+                       NOT EXISTS (SELECT ref_id FROM ttrss_user_entries WHERE ref_id = id)");
 
                if ($do_output) {
                        $rows = db_affected_rows($result);