问题描述

从列值为空的表中获取数据

表：

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));

我要获取member_id = NULL这里的数据。

但是查询写的好像不对

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

解决方案

用这个就能解决：

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