-8021: Column must have DEFAULT specification 

Explanation:

The attempt was made to specify the <action> SET DEFAULT as DELETE rule in a referential CONSTRAINT definition, although no DEFAULT value had been defined for at least one referencing_column.

User Action:

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       1.      If the error occurred during the execution of a CREATE TABLE statement, either define a DEFAULT value for the column(s) or choose another action.

       2.      If the error occurred during the execution of an ALTER TABLE statement, issue another <ALTER TABLE statement> to assign a DEFAULT value to all columns (referencing_column) without a DEFAULT value and then repeat the previous ALTER TABLE statement. Alternatively, you may choose another action.