Difference between revisions of "SET EXCLUSIVE"

Revision as of 14:45, 11 June 2009

Class

Environment

Purpose

Determines whether or not table and index files are opened shareable

Syntax

SET EXCLUSIVE ON | OFF | (<expL>)

See Also

INDEX, MODIFY STRUCTURE, PACK, REINDEX, SET MULTIUSER, USE, ZAP

Description

If SET EXCLUSIVE is ON when a table and its associated index files are opened, then the table and index files cannot be by another user until they are closed. If SET EXCLUSIVE is OFF when a table and its associated index files are opened, then the table and index files are shareable by multiple users.

File and record locking to control concurrent updates to the table and index files is automatically enforced if EXCLUSIVE was OFF when the table was opened. The commands MODIFY STRUCTURE, PACK, REINDEX, INDEX ON (tags) and ZAP are the only commands that require a table to be opened exclusively. By default, EXCLUSIVE is ON.

Example

// Close today’s payments
procedure close_day 
 
set exclusive on
set view to accounts
if used()
    select payments
    set dcache to reccount()
    set dcache on
    seek dtos(date())
    total on dtos(payment_date)+emp_no to (cdow(date));
      while payment_date = date()
    seek dtos(date())
    delete rest while payment_date = date()
    pack
else
    dialog box "Cannot open payments exclusively."
endif
set exclusive off
set view to payments
 
return

Products

Recital Database Server, Recital Mirage Server, Recital Terminal Developer