Spring mongodb template saves in the same object

Question

I have the model like following

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@CompoundIndexes(value = {
        @CompoundIndex(name = "catalog_idx", def = "{'code' : 1, 'brand' : 1}", unique = true) })
@Document(collection = Catalog.ENTITY)
public class Catalog extends AbstractModel<String> {

    private static final long serialVersionUID = 1L;

    public static final String ENTITY = "catalog";

    @NotNull(message = "Code is required")
    @Field("code")
    private String code;

    @NotNull(message = "Brand is required")
    @DBRef(lazy = true)
    @Field("brand")
    private Brand brand;
}

When i do save with mongoTemplate.save(object); i see only 2 objects created in DB instead of 6. Just before save my debug lines for objects to be saved.

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Catalog [code=StagedCatalog, brand=Brand [code=Brand_3]]
Catalog [code=StagedCatalog, brand=Brand [code=Brand_2]]
Catalog [code=StagedCatalog, brand=Brand [code=Brand_1]]
Catalog [code=OnlineCatalog, brand=Brand [code=Brand_2]]
Catalog [code=OnlineCatalog, brand=Brand [code=Brand_1]]
Catalog [code=OnlineCatalog, brand=Brand [code=Brand_3]]

Any ideas why ? I feel the Index unique thing is not working somehow. I want code and brand to be unique combination.

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public abstract class AbstractModel<ID extends Serializable> implements Serializable {

    private static final long serialVersionUID = 1L;

    @Id
    private ID id;
}

Answer 1

You have set a unique index. It means that you will be unable to have 2 documents with the same code and brand.

Now you have set the ID column to ID object. The fact that you have 2 insert instead of 6 means that you use the same ID for 3 insert, something like :

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for (code: {"StagedCatalog","OnlineCatalog"} ) {
    ID id=new ID(...);
    for (brand: {1, 2, 3}){
        Catalog cat=new Catalog();
        cat.setId(id);              // <<== this is wrong, you reuse the same id, you will insert first brand, then update to brand2 and brand3.
        cat.setCode(code);
        cat.setBrand(brand);
        mongoTemplate.persist(cat);
    }
}

To prevent that, you need to:

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Catalog cat=new Catalog();
ID id=new ID(realUniqueId);  // RealuniqueId can be code+brand for instance
cat.setId(id); 
...