Question

我需要从表中提取一些数据

例如：

+-------------+------------+-------------+------------+  
| Code        | Progress   |   QTY       | Faulty     |
+-------------+------------+-------------+------------+  
| A           | 10         |      100    |    0       |                 
+-------------+------------+-------------+------------+
| B           | 1          |      10     |    0       |                 
+-------------+------------+-------------+------------+
| C           | 4          |      0      |    1       |                 
+-------------+------------+-------------+------------+
| D           | 7          |      100    |    0       |                 
+-------------+------------+-------------+------------+


SELECT Code, Progress, QTY, Faulty 
FROM myTable 
WHERE Progress <> 7 AND Progress = 4 AND QTY > 0

如何选择所有记录 - 进展＆lt;＆gt; 7 - 和进度4但仅当具有进度的行的QTY大于0时 - 故障的值是1？

Answer 1

请试一试

SELECT 
Code, 
Progress, 
QTY, 
Faulty 
FROM myTable 
WHERE Progress NOT IN(4,7)
      OR (Progress = 4 AND QTY > 0 AND Faulty = 1)

<强>解释

Progress <> 7之类的条件会带来Progress = 4的记录。该特定记录可能没有QTY > 0 AND Faulty = 1。

这就是为什么使用Progress NOT IN (4,7)作为第一个条件。

现在你需要担心你的第二个案例，就像你提到的那样非常直接。

(Progress = 4 AND QTY > 0 AND Faulty = 1)

将Progress = 4 having QTY >0 and Faulty = 1的记录带入最终结果集。

Answer 2

select * from table
where Progress<>7 
and Progress in (select Progress from table t where QTY>0 and Faulty =1)

在IF子句中选择IF的记录？

2 个答案: