Difference between revisions of "DESCRIPTION Column Constraint"

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==See Also==
 
==See Also==
[[ALTER TABLE]], [[SQL Constraints|CONSTRAINTS]], [[CREATE TABLE]]
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[[ALTER TABLE]], [[SQL Constraints|CONSTRAINTS]], [[CREATE TABLE]], [[LABEL()]]
  
  
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==Example==
 
==Example==
 
<code lang="recital">
 
<code lang="recital">
set sql to recital
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ALTER TABLE customer;
exec sql
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  ADD COLUMN dateref DATE;
ALTER TABLE customer ADD COLUMN dateref date
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  DEFAULT date();
DEFAULT date() DESCRIPTION "Date Reference";
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  DESCRIPTION "Date Reference"
use customer
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list structure
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</code>
 
</code>
  
  
 
==Products==
 
==Products==
Recital Database Server, Recital Mirage Server, Recital Terminal Developer
+
Recital, Recital Server
 
[[Category:Documentation]]
 
[[Category:Documentation]]
 
[[Category:SQL]]
 
[[Category:SQL]]

Latest revision as of 14:38, 25 August 2011

Purpose

Column constraint to set the column description for the specified column


Syntax

DESCRIPTION <expC>


See Also

ALTER TABLE, CONSTRAINTS, CREATE TABLE, LABEL()


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

ALTER TABLE customer;
  ADD COLUMN dateref DATE;
  DEFAULT date();
  DESCRIPTION "Date Reference"


Products

Recital, Recital Server