Question

表1

ID             Qty      completed_qty   KEY
1              2          1              a
2              3          1              b
3              4          3              c

表2

ID             Qty      completed_qty   Percent     Priority         KEY
 1              2            1            50          H               a
 2              3            1           33.33        L               b
 3              4            3            75          H               c

我有2个表，我选择表1，然后使用下面的脚本插入表2

INSERT into table2(Qty, Completed_qty, Percent, KEY)
select Qty, Completed_qty, (completed_qty / Qty) * 100 [Percent], KEY from table1 where
KEY not in (select table2.KEY from table2)

因此，每次执行脚本时，相同的记录都不会复制到table2中当table1的百分比发生变化时我遇到问题，我想更新表2中的百分比，我更改脚本如下但不能成功。

INSERT into table2(Qty, Completed_qty, Percent, KEY)
select Qty, Completed_qty, (completed_qty / Qty) * 100 [Percent], KEY from table1 where 
KEY not in (select table2.KEY from table2)
and (completed_qty / Qty) * 100 <> (select table2.Percent from table2)

我收到如下错误：

子查询返回的值超过1。子查询遵循=，！=，＆lt;，＆lt; =，＆gt;，＆gt; =或子查询用作表达式时不允许这样做

任何人之前都做过类似的剧本。知道我怎么能这样做吗？

Answer 1

这是您的查询：

insert into table2(Qty, Completed_qty, Percent, KEY)
    select Qty, Completed_qty, (completed_qty / Qty) * 100 [Percent], KEY
    from table1
    where KEY not in (select table2.KEY from table2) and
          (completed_qty / Qty) * 100 <> (select table2.Percent from table2)
-----------------------------------------^

第二个子查询是问题所在。我怀疑你想要not in：

insert into table2(Qty, Completed_qty, Percent, KEY)
    select Qty, Completed_qty, (completed_qty / Qty) * 100 [Percent], KEY
    from table1
    where KEY not in (select table2.KEY from table2) and
          (completed_qty / Qty) * 100 not in (select table2.Percent from table2 where table2.Percent is not null)

使用is not null时，额外的not in非常重要。否则，NULL中的table2.Percent值将会过滤掉每一行。

Answer 2

您可以在那里使用NOT IN条款

and (completed_qty / Qty) * 100 NOT IN (select table2.Percent from table2)

修改

您可以在NULL列中插入Percent，如下所示

INSERT into table2(Qty, Completed_qty, Percent, KEY) select Qty, Completed_qty, null, KEY from table1 where KEY not in (select table2.KEY from table2)

稍后再做UPDATE

UPDATE table2 a JOIN table1 b ON a.key = b.key SET a.Percent = (b.completed_qty / b.Qty) * 100 WHERE a.Percent IS NULL

Answer 3

您收到错误是因为子查询返回了多个结果。您可以使用NOT IN代替<>。

但是，根据您的陈述I want update also the Percent in table 2。如果table2发生更改并且密钥已存在于table1中，您似乎想要更新table2。在这种情况下，您需要使用UPDATE查询：

UPDATE table2 t2
JOIN table1 t1 on t2.key = t1.key
SET Percent = t1.completed_qty / t1.Qty * 100

Answer 4

如果表中有很多行，则查询速度会很慢。

试试这个：

Insert into table2(Qty, Completed_qty, Percent, KEY)
Select a.Qty, a.Completed_qty, (a.completed_qty / a.Qty) * 100 [Percent], a.KEY 
From table1 a
Left Join table2 b On b.KEY = a.KEY
Where b.KEY is Null
    Or
    ( b.KEY is Not Null and ((a.completed_qty / a.Qty) * 100) <> b.Percent )

SQL插入（从中选择）

4 个答案: