-593   NOT NULL MUST BE SPECIFIED FOR column-name BECAUSE IT IS DEFINED AS A ROWID (OR DISTINCT TYPE FOR ROWID), ROW CHANGE TIMESTAMP COLUMN, ROW BEGIN COLUMN, ROW END COLUMN, OR COLUMN OF A PERIOD column-name

The NOT NULL clause was specified for a column whose type does not permit null values.

column-name

The name of the column that requires the NOT NULL clause.

The following columns do not permit null values:

• ROWID columns
• Distinct type columns for which the source type is ROWID
• Row change timestamp columns
• Row begin columns and row end columns
• Columns of a period

When one of these columns is defined on a CREATE TABLE, ALTER TABLE, or DECLARE TABLE statement, the NOT NULL clause must be specified for the column.