-7038: Foreign key column not allowed 

Explanation:

A foreign key column is a column which was specified in the referencing_column of a referential CONSTRAINT definition.

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       1.      The attempt was made to delete a table column which was specified as a referencing_column of a CONSTRAINT definition.

       2.      The attempt was made to delete the key of a table. The columns of the key were specified implicitly or explicitly as referencing_columns of a CONSTRAINT definition.

User Action:

Delete the referential CONSTRAINT definition and then the column or key.