Do foreign keys affect query speed?

That's the whole question. Do foreign keys (FKs) affect query speed? 'Course the answer could lead to sub-questions , e.g., "If so, how best to optimize a query for them?" And I guess a corollary question would be whether implementing FKs slows down MySQL processing in general, but that can pro

Do foreign keys affect query speed?

That's the whole question. Do foreign keys (FKs) affect query speed? 'Course the answer could lead to sub-questions , e.g., "If so, how best to optimize a query for them?" And I guess a corollary question would be whether implementing FKs slows down MySQL processing in general, but that can pro