Extra returned when analyzing explain of MySQL: Impossible WHERE noticed after reading const tables
because I used the primary key id query, but this primary key does not exist. But I don"t know if this will slow down the query. If it slows down the query, do any bosses know how to solve it?
the line you queried does not exist, how can it slow down the query? Const should be fast
figure this situation will not slow down the query, if it is where name='xxx' and name does not have an index, type as ALL, causes a full table scan to slow down the query.
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