Android的删除查询 [英] Android Delete Query

问题描述

我试图删除一个表中没有在另一个表中的相应的ID的所有行。因为显然SQLite不支持加盟删除我试图做沿着这些路线的东西：

I'm attempting to delete all rows in one table that do not have a corresponding ID in another table. Since apparently SQLite does not support joins in deletes I am trying to do something along these lines:

    DELETE FROM my_table WHERE my_id NOT IN (SELECT _id FROM my_table2);

不过，我显然不能用rawQuery，因为它返回一个指针，所以我必须使用删除功能。我有一些麻烦这个工作。这是我想要的查询：

However, I apparently can not use rawQuery since it returns a cursor so I have to use the delete function. I'm having some trouble getting this working. Here is the query I'm trying:

    mDb.delete("my_table", "my_id NOT IN ?", new String[]{"(SELECT _id FROM my_table2)"});

感谢。

推荐答案

您不应使用.rawQuery，如你所说，但您可以使用.execSQL（）来完成它。我经常用它来删除自己。

You shouldn't use a .rawQuery, as you stated, but you can use .execSQL() to accomplish it. I regularly use it for deletions myself.

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