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Add constraint that ensures that a key field is unique in a collection #13

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hisystems opened this Issue Mar 4, 2012 · 0 comments

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hisystems commented Mar 4, 2012

A key field is typically a value that a user can enter and modify. For example, a product code from a products table. This constraint should ensure:

  • if the object is new, that the key value has not already been used in the table / table subset
  • if the value has changed, then the new value does not conflict with an existing value already in the table / table subset.
    This constraint should encapsulate this concept and eliminate the need to repeatedly resolve this problem for different tables and scenarios.
  • if the value has not changed then the constraint passes

@ghost ghost assigned hisystems Mar 4, 2012

@hisystems hisystems closed this in 7ff02b6 Mar 10, 2012

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