DESCRIPTION Column Constraint

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DESCRIPTION

Class

Column Constraints


Purpose

Column constraint to set the column description for the specified column


Syntax

DESCRIPTION <expC>


See Also

ALTER TABLE, CONSTRAINTS, CREATE TABLE


Description

A constraint is used to define rules that help to provide data integrity. Column constraints are specific to the column name specified. You must have ALTER privilege on the table. The table will be locked for EXCLUSIVE use during the operation.

The DESCRIPTION column constraint is used to set the column description for the specified column. The <expC> is a character expression of up to 25 characters.


Example

set sql to recital
exec sql
ALTER TABLE customer ADD COLUMN dateref date
DEFAULT date() DESCRIPTION "Date Reference";
use customer
list structure


Products

Recital Database Server, Recital Mirage Server, Recital Terminal Developer