这是我的查询
select PhoneNumber as _data,PhoneType as _type from contact_phonenumbers where ContactID = 3 and Type = 'R' and PT = 'M'
union
SELECT EmailID,Type from contact_emails where ContactID = 3 and Type = 'P'
UNION
SELECT EmailID,Type from contact_emails where ContactID = 3 and Type = 'O'
这里我的问题是我需要从每个select语句中只获取一行。是否可以通过“限制”获取它。
答案 0 :(得分：5)
根据MySQL网站，您可以将限制应用于个人选择
(SELECT a FROM t1 WHERE a=10 AND B=1 ORDER BY a LIMIT 10)
UNION
(SELECT a FROM t2 WHERE a=11 AND B=2 ORDER BY a LIMIT 10);