-7004: DEFAULT not allowed 

Explanation:

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       1.      Columns with DEFAULT specification cannot be added to a table with the ALTER TABLE statement.

       2.      The specification of NOT NULL DEFAULT NULL is not allowed.

User Action:

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       1.      To add a column to one with an <ALTER TABLE statement>, specify it without a DEFAULT specification. Then define the DEFAULT in another <ALTER TABLE statement>. This how this column is given the DEFAULT value in all table rows.

       2.      Delete the DEFAULT specification from the SQL statement and execute the statement again.