本课内容目前为英文。
Why is this query slow?
A query that takes 2 ms on a thousand rows can take 2 seconds on ten million. Indexes fix that, and EXPLAIN shows you whether they are actually being used.
本课内容目前为英文。
A query that takes 2 ms on a thousand rows can take 2 seconds on ten million. Indexes fix that, and EXPLAIN shows you whether they are actually being used.