sql - sql综合查询

Question

早上好。谁能帮我查询一下，总结每个表（表1 +表2）中的总代码，如表3所示，非常感谢。对不起，我的英语不好

标签： sql

Answer 1

SELECT A.code, count(A.Date) as bang_1 , B.bang_2
FROM table_1 A
LEFT JOIN (SELECT code,count(*) as bang_2 
           FROM table_2
           GROUP BY code) B ON A.code = B.code
GROUP BY A.code, B.bang_2