如何在SQL查询中替换UNION

Question

我有一张桌子：attb

------------------------------------------------
Id | Name | Code | Attribute | Amount 
------------------------------------------------
1  | AV   | 123  | Alpha     | 233
------------------------------------------------
2  | TV   | 122  | Beta      | 235
------------------------------------------------
3  | TV   | 123  | Gama      | 238
------------------------------------------------
4  | CD   | 122  | Beta      | 239
------------------------------------------------
5  | TP   | 122  | Beta      | 240
------------------------------------------------
6  | RX   | 123  | Alpha     | 241
------------------------------------------------

我以以下方式查询它：

select id,name, code, attribute, amount
from attb
where code = 123 and attribute='Alpha'
UNION
select id,name, code, attribute, amount
from attb
where code = 122;

它返回以下内容

---

Id | Name | Code | Attribute | Amount 
------------------------------------------------
1  | AV   | 123  | Alpha     | 233
------------------------------------------------
2  | TV   | 122  | Beta      | 235
------------------------------------------------
4  | CD   | 122  | Beta      | 239
------------------------------------------------
5  | TP   | 122  | Beta      | 240
------------------------------------------------
6  | RX   | 123  | Alpha     | 241
------------------------------------------------

有没有一种方法可以合并两个查询而不是使用UNION运算符？或任何更好的实现？

Answer 1

只需将两个%子句放在一个查询中：

where

输出：

select id,name, code, attribute, amount
from attb
where (code = 123 and attribute='Alpha') 
   or code = 122;

SQLFiddle demo

Answer 2

非常容易。只需使用modules/。

or

Answer 3

尝试一下。

select id,name, code, attribute, amount
    from attb
    where ((code = 123 and attribute='Alpha') or (code = 122))

Answer 4

select id,name, code, attribute, amount
from attb
where (code IN(122, 123) and attribute='Alpha') ;