oracle 如何在Oracle中有条件插入？
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How to insert conditionally in Oracle?
提问by Kamil
I've read herethat the syntax looks like this:
我在这里读到语法如下所示：
INSERT
WHEN ([Condition]) THEN
INTO [TableName] ([ColumnName])
VALUES ([VALUES])
ELSE
INTO [TableName] ([ColumnName])
VALUES ([VALUES])
SELECT [ColumnName] FROM [TableName];
But I don't want to provide values from another table. I just want to type them, so I've got:
但我不想提供另一个表中的值。我只想输入它们，所以我有：
INSERT
WHEN EXISTS (SELECT 1 FROM FOO WHERE NAME = 'JOE')
THEN
INTO BAR (NAME, AGE)
VALUES ('JOE', 50)
and this produces exception: ORA-00928: missing SELECT keyword.
这会产生异常：ORA-00928：缺少 SELECT 关键字。
I want to perform an insert if given value is found in another table.
如果在另一个表中找到给定值，我想执行插入。
采纳答案by hkutluay
using with select also running. but there is a problem with values keyword
与 select 一起使用也在运行。但是 values 关键字有问题
INSERT
WHEN EXISTS (SELECT 1 FROM FOO WHERE NAME = 'JOE')
THEN
INTO BAR (NAME, AGE)
SELECT 'JOE', 50 FROM DUAL
回答by Kamil
So, I've found an indirect way hereand solution for my question would be:
所以，我在这里找到了一种间接的方法，我的问题的解决方案是：
INSERT INTO BAR (NAME, AGE)
SELECT 'JOE', 50
FROM DUAL
WHERE EXISTS (SELECT 1 FROM FOO WHERE NAME = 'JOE')
but it doesn't explain why I have to use SELECTstatement in INSERT WHEN
但它并没有解释为什么我必须SELECT在INSERT WHEN
