使用leftJoin多表聯(lián)查,最后select的字段里有一個(gè)字段是其中一個(gè)右表里count出來(lái)的字段,但如果那個(gè)表里沒(méi)有count數(shù)據(jù),整個(gè)查詢(xún)會(huì)丟掉結(jié)果,現(xiàn)在想的是如果查詢(xún)沒(méi)有結(jié)果則保留左表數(shù)據(jù)。大概代碼是這樣:SELECT a.name,COUNT(b.id) AS com FROM `a` LEFT JOIN `b` ON `a`.`uid` = `b`.`uid` LEFT JOIN `c` ON`d`.`id` = `c`.`id` ORDER BY `a`.`id` DESC LIMIT 10 OFFSET 0最后如果b里沒(méi)有對(duì)應(yīng)數(shù)據(jù) 則會(huì)丟掉查詢(xún)的數(shù)據(jù)
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