如何从列中等于NULL的表中获取数据

Question

我有桌子:

CREATE TABLE Reports (
         _id INTEGER NOT NULL PRIMARY KEY,member_id INTEGER, 
      is_conf BOOLEAN,
         name TEXT, 
      started INTEGER,

     finished INTEGER,
    description TEXT, 
       obj_id INTEGER NOT NULL, 
     FOREIGN KEY (obj_id) REFERENCES Objects (_id));

我想把数据拿到哪里member_id = NULL.
但查询:

String sql = "SELECT _id, name FROM Reports WHERE member_id = NULL";
Cursor cursor = db.rawQuery(sql, null);

不起作用.

Answer 1

你需要使用这个:

String sql = "SELECT _id, name FROM Reports WHERE member_id IS NULL";