In case you have your own slow SQL query, you can optimize it automatically here.
For the query above, the following recommendations will be helpful as part of the SQL tuning process.
You'll find 3 sections below:
ALTER TABLE `lds_order_status` ADD INDEX `lds_status_idx_status_po_no` (`status`,`PO_NO`);
ALTER TABLE `lds_order_status` ADD INDEX `lds_status_idx_po_no` (`PO_NO`);
SELECT
lds_order_status.PO_NO
FROM
lds_order_status
WHERE
lds_order_status.status = 'CLOSED'
GROUP BY
lds_order_status.PO_NO
ORDER BY
lds_order_status.PO_NO