Difference between revisions of "ONUPDATE Table Constraint"
Helengeorge (Talk | contribs) (→Products) |
Yvonnemilne (Talk | contribs) |
||
| Line 19: | Line 19: | ||
==Example== | ==Example== | ||
<code lang="recital"> | <code lang="recital"> | ||
| − | ALTER TABLE customer modify ONUPDATE "p_update" | + | ALTER TABLE customer; |
| + | modify ONUPDATE "p_update" | ||
</code> | </code> | ||
Latest revision as of 11:04, 22 December 2009
Purpose
Table constraint activated when an attempt is made to update a record in the table
Syntax
ONUPDATE <procedure>
See Also
ALTER TABLE, CONSTRAINTS, CREATE TABLE
Description
A constraint is used to define rules that help to provide data integrity. TABLE constraints apply to table-based operations. You must have ALTER privilege on the table. The table will be locked for EXCLUSIVE use during the operation.
The ONUPDATE table constraint is activated when an attempt is made to update a record in the table. The <procedure> specified must be a character expression evaluating to a procedure name. If no file extension is included, '.prg' is assumed. The specified procedure is run before the operation to update the record is executed and must return True (.T.) or the update operation is cancelled.
Example
ALTER TABLE customer; modify ONUPDATE "p_update"
Products
Recital, Recital Server
