android 房间数据库架构无效错误导致primaryKeyPosition

Question

I have a simple database with few tables.i have implemented room entities for tables.i'm getting this error and it's saying that my schema is invalid.but i found it very similar only difference is column order and primaryKeyPosition.

error message(i have omitted the foreign keys as they are equal)

Expected:

TableInfo{name='am',
 columns={name=Column{name='name', type='TEXT', affinity='2', notNull=false, primaryKeyPosition=0, defaultValue='null'},
 symbol=Column{name='symbol', type='TEXT', affinity='2', notNull=false, primaryKeyPosition=0, defaultValue='null'},
 a_number=Column{name='a_number', type='INTEGER', affinity='3', notNull=true, primaryKeyPosition=1, defaultValue='null'},
 a_id=Column{name='a_id', type='INTEGER', affinity='3', notNull=true, primaryKeyPosition=0, defaultValue='null'}},


Found:

TableInfo{name='am',
 columns={symbol=Column{name='symbol', type='TEXT', affinity='2', notNull=false, primaryKeyPosition=0, defaultValue='null'},
 name=Column{name='name', type='TEXT', affinity='2', notNull=false, primaryKeyPosition=0, defaultValue='null'},
 a_number=Column{name='a_number', type='INTEGER', affinity='3', notNull=true, primaryKeyPosition=1, defaultValue='null'},
 a_id=Column{name='a_id', type='INTEGER', affinity='3', notNull=true, primaryKeyPosition=2, defaultValue='null'}},

i have attached a image to clarify the difference

as you can see only differences are * 1st and 2nd table column order is different * primaryKeyPosition is different in last column

my entity class

@Entity(tableName = "am",
        foreignKeys = {
                @ForeignKey(entity = ATypes.class,
                        parentColumns = "a_id",
                        childColumns = "a_id"),
        },
        indices = {@Index("a_id")}
)
public class Am {

    public String name;
    public String symbol;
    @PrimaryKey
    @ColumnInfo(name = "a_number")
    public int aNumber;

    @NonNull
    @ColumnInfo(name = "a_id")
    public Integer aId;

}

my question how can i change the column order or primaryKeyPosition in order to match expected schema.

Answer 1

You are missing the index for your primary key!

Answer 2

If you are using Robolectric the problem may be caused by this issue https://github.com/robolectric/robolectric/issues/4209

I had the same issues and I solved it with https://github.com/guness/RobolectricSQLite