PostgreSQL中不存在语法错误 [英] WHERE NOT EXISTS in PostgreSQL gives syntax error
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问题描述
当尝试使用 WHERE NOT EXISTS
子句来防止在 age
,我在 WHERE处或附近收到错误语法错误。
When trying to use the WHERE NOT EXISTS
clause to prevent adding a row with a duplicate value in the column age
, I get the error syntax error at or near "WHERE"
.
为什么会引发语法错误?我正在使用Postgresql 9.1。
Why did it throw a syntax error? I'm using Postgresql 9.1.
SQL
INSERT INTO live.users ("website", "age")
values ('abc', '123')
WHERE NOT EXISTS (SELECT age FROM live.users WHERE age = 123);
错误
ERROR: syntax error at or near "WHERE"
LINE 6: WHERE NOT EXISTS (SELECT age FROM live.users W...
推荐答案
执行以下操作:
INSERT INTO live.users ("website", "age")
SELECT 'abc', 123
WHERE NOT EXISTS (SELECT age FROM live.users WHERE age = 123);
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