Difference between revisions of "DEFAULT Column Constraint"

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==Example==
 
==Example==
 
<code lang="recital">
 
<code lang="recital">
set sql to recital
+
ALTER TABLE customer;
exec sql
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  ADD COLUMN dateref DATE DEFAULT date()
ALTER TABLE customer ADD COLUMN dateref date DEFAULT date();
+
use customer
+
list dictionary
+
 
</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 11:20, 22 December 2009

Purpose

Column constraint to set a default value for the specified column


Syntax

DEFAULT <expr>


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 DEFAULT column constraint is used to set a default value for the specified column. The <expr> must evaluate to the same data type as the target column. The column's value can subsequently be updated.


Example

ALTER TABLE customer;
  ADD COLUMN dateref DATE DEFAULT date()


Products

Recital, Recital Server