java - 安卓房间: One database with multiple tables

Question

我的应用程序有两个单独的表，一个称为用户，另一个称为密​​码。

用户:

@Entity(tableName = "users")
public class Users {
   // some setters and getters here
}

密码:

@Entity(tableName = "passwords")
public class Passwords {
   // some setters and getters here
}

这就是我访问数据库的方式:

usersdb = Room.databaseBuilder(this, Users.class,"mymaindb")
          .allowMainThreadQueries()
          .build();

// Then later in some other activity when I need to use passwords table

passwords = Room.databaseBuilder(this, passwords.class,"mymaindb")
          .allowMainThreadQueries()
          .build();

我遇到的问题是，全新安装后，当我访问密码时，我无法访问用户，反之亦然。

我收到以下错误:

Caused by: java.lang.IllegalStateException: Room cannot verify the data integrity. Looks like you've changed schema but forgot to update the version number. You can simply fix this by increasing the version number.

但是当我尝试拥有两个独立的数据库(例如passwords_db和users_db)而不是mymaindb时，它工作得很好。

那么有没有一种方法可以在一个数据库下拥有多个表？如果是这样，那我做错了什么？提前致谢!

Answer 1

我认为您完全错了，Room.databaseBuilder 应该只调用一次来设置数据库，并且在该数据库类中，您将构造多个表。例如:

Room.databaseBuilder(this, MyRoomDb.class, "mymaindb")
                .allowMainThreadQueries()
                .build()

你的MyRoomDb应该看起来像这样

@Database(
        entities = {
            Users.class,
            Passwords.class
        },
        version = VERSION
)
public abstract class MyRoomDb extends RoomDatabase {
...
}