获取造成SQLiteConstraintException约束的名字 [英] Get name of constraint which caused SQLiteConstraintException

问题描述

我如何得到这引起了SQLiteConstraintException约束的名称。

How do I get the name of the constraint which caused the SQLiteConstraintException.

调用toString（）的异常只是给了我：错误code 19：约束失败

Calling toString() on the exception just gives me: "error code 19: constraint failed"

和存在的例外都没法得到的原因。这使得很难调试我的sql。

And there is no method in the exception to get the cause. This makes it rather difficult to debug my sql.

推荐答案

版本 3.7.17开始，SQLite的显示错误消息约束的名称：

Beginning with version 3.7.17, SQLite shows the name of the constraint in error messages:

sqlite> create table t(x, constraint x_positive check (x>0));
sqlite> insert into t values(-1);
Error: constraint x_positive failed

不过，这将是一段时间，在此之前的版本出现在Android的。

However, it will be some time before this version shows up in Android.

在此期间，你可以更换一个触发，可以使用约束任何消息时，它喜欢的：

In the meantime, you could replace the constraint with a trigger that can use whatever message it likes:

CREATE TRIGGER check_x_positive
BEFORE INSERT ON t                -- also UPDATE
FOR EACH ROW
WHEN NEW.x <= 0
BEGIN
    SELECT RAISE(ABORT, 'RED ALERT! database on fire because x <= 0');
END;

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