mysql - 求一个sql语句，比较简单。

Answer 1

select j.*, (select count(*) from submitjobs s where j.id=s.jobid) from jobs j

Answer 2

mysql 为例：select a.*,count(b.userid)sbtotal from jobs a left join sumbmitjobs b on b.jobid=a.id gourp by b.jobid order b.userid

oracle 差不多 只是不能那样分组需要先分组sumbmitjobs 统计好然后作为子查询

Answer 3

SELECT COUNT(DISTINCT column(jobName)) FROM jobs LEFT JOIN submitjobs ON jobs.jobName=submitjobs.jobName

Answer 4

select b.name, a.cnt from 
jobs b left join (select jobid, count(userid) as cnt
from submitjobs
group by jobid) a
on b.id = a.jobid

Answer 5

没测试...

SELECT j.id, j.name, COUNT(sj.jobid) AS count
FROM `submitjobs`
AS sj
JOIN `jobs`
AS j
WHERE sj.jobid = j.id
GROUP BY sj.jobid

Answer 6

其实最简单

 select 想要的字段 from 表1,表2 ...表N  

此种写法不管有多少表都能连起来