this is a function of asking and answering questions
questions asked by users in Table A
questions answered by users in Table B
Table An is the only question corresponding to ID,
Table B PID corresponds to Table An ID users answer which question PID is which question ID
now need to output popular answer this function, that is, to pass which question is answered more times, in order to order
it is done by yourself, but it is too stupid and consumes performance. I hope you can help
for example, table An is: questions, B, table is answers
then SQL is
select a.id, a.title, count(b.pid) as answer_count from questions a, answers b where a.id=b.pid group by b.pid order by answer_count DESC;Previous: About vertx, java.net.BindException: Address already in use
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