Hi Guys,
More a curiosity question than an issue or concern.
Due to a Server PC issue a Customer just rebooted his server pc.
After he had, he did a backup of his EDB Database..
{code}
       DBSBackup.Execute('BACKUP DATABASE "DBiWorkflow" AS "DBiWorkflow-Manual Full Backup - ' + FormatDateTime('yyyy-mm-dd @ HHnn',
         Now) + '" TO STORE "Backups" COMPRESSION 9 INCLUDE CATALOG');
{code}

He then did what we call a 'Maint' which consists of..
{code}
   DBC1.Execute('Repair Table ' + aDataTables[nXt, 0]);
{code}
then
{code}
     DBC1.Execute('Optimize Table ' + aDataTables[nXt, 0] + ' No Backup Files')
{code}
on each of the 28 tables in the database.

He then did another backup.

So here's the curiosity...  
Backup size before 'Maint' = 1,087,676,207 Bytes.
Backup size after 'Maint'    = 1,201,478,514 Bytes.

Why such a large difference??

Regards,
Ian

a

Ian


I'll be interested to hear the answer. My guess is that there was some "corruption". The backup copies what it can "see" in the tables and after repairing it can see more.

You might want to add a VERIFY TABLE in as part of the routine a) because if there's no problem don't repair and b) so you have a record of any problems that did exist

Roy Lambert

Ian,

<< He then did another backup.

So here's the curiosity...  
Backup size before 'Maint' = 1,087,676,207 Bytes.
Backup size after 'Maint'    = 1,201,478,514 Bytes.

Why such a large difference?? >>

OPTIMIZE TABLE will physically reorganize the table and rebuild the indexes, and this can definitely affect how the compression works.

Tim Young
Elevate Software
www.elevatesoft.com