我有多个 insert into..select 语句,如下所示。如果您看到的话,所有三个语句中只有一列值 (Req_Attrname) 发生变化。其他一切都相同,包括 where
条件。
插入语句1)
insert into details(repo_phyid,repo_type,repo_attrname,repo_Attrvalue
,Req_phyid,Req_type,Req_Attrname,Req_attrvalue)
select demo.phyid,'Complementary Item','Product Management Responsible',demo.attr_value,
tnr.phyid,'Complementary Item','**Product Manager**',demo.attr_value
From repo_Tnr Tnr,repo_Tnr_Attribute demo
Where Tnr.Phyid=demo.Phyid
And demo.Attr_Name='Product Management Responsible'
and tnr.type='Complementary Item'
插入语句2)
insert into details(repo_phyid,repo_type,repo_attrname,repo_Attrvalue,
Req_phyid,Req_type,Req_Attrname,Req_attrvalue)
select demo.phyid,'Complementary Item','Product Management Responsible',demo.attr_value,
tnr.phyid,'Complementary Item','**Quality Manager**',demo.attr_value
From repo_Tnr Tnr,repo_Tnr_Attribute demo
Where Tnr.Phyid=demo.Phyid
And demo.Attr_Name='Product Management Responsible'
and tnr.type='Complementary Item'
插入语句3)
insert into details(repo_phyid,repo_type,repo_attrname,repo_Attrvalue
,Req_phyid,Req_type,Req_Attrname,Req_attrvalue)
select demo.phyid,'Complementary Item','Product Management Responsible',demo.attr_value
,tnr.phyid,'Complementary Item',**'Depty Engineer**',demo.attr_value
From repo_Tnr Tnr,repo_Tnr_Attribute demo
Where Tnr.Phyid=demo.Phyid
And demo.Attr_Name='Product Management Responsible'
and tnr.type='Complementary Item'
我在这里尝试的是,如果选择返回 20 行,首先我必须插入 20 行,并将 Product Manager
作为 Req_attrname 的值,然后我必须插入相同的 20 行,但是与质量经理
合作,并再次与副工程师
合作。为了实现这一点,我使用了 3 个插入语句。像这样我有 15 到 20 个插入语句。有没有一种方法可以在单个插入语句中做到这一点?它将帮助我减少代码并增加可读性。请提供替代解决方案。
最佳答案
由于 Req_Attrname
都是常量,因此您可以从 dual
查询所有这些内容,并在原始查询上交叉连接
此结果,以便您获取查询中的每一行与每个 Req_Attrname
匹配的行:
INSERT INTO details (repo_phyid,
repo_type,
repo_attrname,
repo_attrvalue,
req_phyid,
req_type,
req_attrname,
req_attrvalue)
SELECT demo.phyid,
'Complementary Item',
'Product Management Responsible',
demo.attr_value,
tnr.phyid,
'Complementary Item',
req_attrname,
demo.attr_value
FROM repo_tnr tnr
JOIN repo_tnr_tttribute demo ON tnr.phyid = demo.phyid
CROSS JOIN (SELECT '**Product Manager**' AS req_attrname FROM dual
UNION ALL
SELECT '**Quality Manager**' AS req_attrname FROM dual
UNION ALL
SELECT '**Depty Engineer**' AS req_attrname FROM dual) t
WHERE demo.attr_name = 'Product Management Responsible' AND
tnr.type = 'Complementary Item'
关于sql - 如何在单个插入语句中执行多个 insert into..select 查询?,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/31470243/