Nested relationships in Room

Question

I have entities:

@Entity
public class Item {
    @PrimaryKey(autoGenerate = true)
    public long id;
    public String value;
}

@Entity
public class Image {
    @PrimaryKey(autoGenerate = true)
    public long id;
    public String value;
    public long patternId;
    public long itemId;
}

@Entity
public class Pattern {
    @PrimaryKey(autoGenerate = true)
    public long id;
    public String value;
}

And relations:

public class ItemWithImages {
    @Embedded
    public Item item;

    @Relation(parentColumn = "id", entityColumn = "itemId")
    public List<ImageWithPattern> imageWithPattern;
}

public class ImageWithPattern {
    @Embedded
    public Image image;

    @Embedded
    public Pattern pattern;
}

Dao query:

Query("SELECT * FROM items LEFT JOIN patterns ON images.patternId = patterns.id")
public abstract Maybe<List<ItemWithImages>> getItems();

And here is my error:

There is a problem with the query: [SQLITE_ERROR] SQL error or missing database (no such column: images.pattern_id)

In case anyone is interested in the answer, check it out [Answer](https://stackoverflow.com/a/52554115/4980713) — Edy Daoud, Dec 12 '18 at 12:18
@EdyDaoud Why do you keep posing this? This is not the answer to this question — PrashanD, Apr 29 '19 at 17:46
I am also interested in the right answer for this problem. @PrashanD do you have any ideas you could share? — Eduardo, Jun 02 '19 at 14:14
@Eduardo https://stackoverflow.com/a/46423137/1800515 worked for me — PrashanD, Jun 03 '19 at 07:30

Nested relationships in Room

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