我一直在寻找它,但找不到所需的东西.我在android中有一个sqlite表,我想知道rawquery对于多个WHERE子句的影响.我的意思是,我想知道一个表的所有记录以及其中两个列的值为1的那些列的所有列.
我该怎么办?
我试过了:
String selectQuery = "SELECT * FROM " + TABLE_NAME
+ " WHERE " + KEY_ONE + " = " + String.valueOf(var1)
+ " AND WHERE " + KEY_TWO + " = " + String.valueOf(Var2);
sqliteDatabase db = this.getWritableDatabase();
Cursor cursor = db.rawQuery(selectQuery, null);
但这不起作用..
感谢您的帮助:D
解决方法:
删除第二个WHERE:
+ " AND " + KEY_TWO + " = " + String.valueOf(Var2);
还要注意,字符串必须用撇号引起来:
String selectQuery = "SELECT * FROM " + TABLE_NAME
+ " WHERE " + KEY_ONE + " = '" + String.valueOf(var1)
+ "' AND " + KEY_TWO + " = '" + String.valueOf(Var2) + "'";
如果使用以下增强语法,那就更好了:
String selectQuery = "SELECT * FROM " + TABLE_NAME
+ " WHERE " + KEY_ONE + " = ? AND " + KEY_TWO + " = ?";
sqliteDatabase db = this.getWritableDatabase();
Cursor cursor = db.rawQuery(selectQuery, new String[]{String.valueOf(var1), String.valueOf(var2)});