Notice: Trying to access array offset on value of type null in /mnt/raid/webserver/virtual/ on line 40

Notice: Undefined offset: 1 in /mnt/raid/webserver/virtual/ on line 40
Could not successfully run query (SELECT filename FROM rets_mls_images WHERE mls = ) from DB: You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near '' at line 1