Facets answered exactly one question — how many documents per term, per range, per date interval — and could not be nested, so a sidebar showing brands within…
A query that used the right index all week starts using a different one on Thursday morning, nothing was deployed, and ANALYZE TABLE puts it back. Before 5.6,…
WP_Query covers a lot and stops short of a few things: ordering by a joined table, a GROUP BY you chose, an index hint, a comparison meta_query cannot…
A relation read inside a loop issues a query per iteration. Fifty orders rendered with the customer name attached is fifty-one queries, and nothing on the page says…
A slow query log at the usual one-second threshold shows the report that takes four seconds and hides the nine hundred queries of eight milliseconds that the product…
A daily report scanning 1.2 million rows to return two hundred. Why neither obvious index helped, what the composite one costs, and the two answers I turned down.