# Common database issues

## 10.9.0: Duplicate definition field names on definitions

When migrating to Ucommerce Next Gen >10.9.0, you might encounter the following error:

{% code overflow="wrap" %}

```
Ucommerce database migration failed with message The CREATE UNIQUE INDEX statement terminated because a duplicate key was found for the object name 'dbo.uCommerce_DefinitionField' and the index name 'UX_uCommerce_DefinitionField_DefinitionId_Name'. The duplicate key value is (1, Organization). The statement has been terminated., in script 117 - Create missing unique indexes on definition fields
```

{% endcode %}

This means that you have multiple definition fields with the same name for the same definition. This makes the data ambiguous and should be avoided. Unfortunately, we cannot know what data is correct and apply automatic corrections. Instead, what you have to do is clean up the database manually before proceeding with the migration.

Fortunately we have made this task easy for you. To find the duplicates that needs to be cleaned up, run the following scripts:

{% code title="Product definitions" overflow="wrap" %}

```sql
SELECT pdf.* FROM uCommerce_ProductDefinitionField as pdf 
INNER JOIN ( 
    SELECT [ProductDefinitionId], [Name] 
    FROM [uCommerce_ProductDefinitionField] 
    GROUP BY ProductDefinitionId, Name 
    HAVING COUNT(*) > 1 
) AS Duplicates ON pdf.ProductDefinitionId = Duplicates.ProductDefinitionId AND pdf.Name = Duplicates.Name
ORDER BY Name, ProductDefinitionId
```

{% endcode %}

{% code title="Other definitions" overflow="wrap" %}

```sql
SELECT df.* FROM uCommerce_DefinitionField as df 
INNER JOIN ( 
    SELECT [DefinitionId], [Name] 
    FROM [uCommerce_DefinitionField] 
    GROUP BY DefinitionId, Name 
    HAVING COUNT(*) > 1 
) AS Duplicates ON df.DefinitionId = Duplicates.DefinitionId AND df.Name = Duplicates.Name
ORDER BY Name, DefinitionId
```

{% endcode %}


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