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From:Ingo Strüwing Date:September 21 2009 3:43pm
Subject:MOM-BACKUP-090901 action items closed - decision required
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Hi Lars,

please mark my action items in the minutes-of-meeting from the
2009-09-01 backup meeting as closed.

1. I verified that it is not possible with plain INSERT and ALTER
statements to generate duplicate key errors on AUTO_INCREMENT columns.
The key part of this behavior is that ALTER does never set an
AUTO_INCREMENT value less or equal to the highest key value.

2. I tested that mysqldump creates SQL files that restore the
AUTO_INCREMENT value properly when fed to the mysql utility. The key
part of this behavior is that it uses INSERT statements to load the
data. These update the AUTO_INCREMENT value properly.

3. I reported Bug#47484 (Online Backup: Restore does not set the
auto_increment value correctly). The main problem is that BACKUP/RESTORE
does not use full INSERT statements to restore the table data. The
AUTO_INCREMENT value is left at 1. Later INSERTs that use the wrong
AUTO_INCREMENT value receive duplicate key errors. One successful INSERT
with explicit key value fixes the AUTO_INCREMENT value for that table.

Item 3 may require a new team decision. We may not want to live with
difficult to use InnoDB tables after RESTORE.

We can perhaps fix this by using the "metadata-extra" information per
table to transport the AUTO_INCREMENT values. This might work without an
image file format change.

I will not push Bug#42895/WL#4844 (Implement a locking scheme for
RESTORE) without a new decision.

Regards
Ingo
-- 
Ingo Strüwing, Database Group
Sun Microsystems GmbH, Sonnenallee 1, D-85551 Kirchheim-Heimstetten
Geschäftsführer: Thomas Schröder,   Wolfgang Engels,   Wolf Frenkel
Vorsitzender des Aufsichtsrates: Martin Häring   HRB München 161028
Thread
MOM-BACKUP-090901 action items closed - decision requiredIngo Strüwing21 Sep
  • Re: MOM-BACKUP-090901 action items closed - decision requiredRafal Somla22 Sep
    • Re: MOM-BACKUP-090901 action items closed - decision requiredIngo Strüwing22 Sep
      • Re: MOM-BACKUP-090901 action items closed - decision requiredRafal Somla22 Sep
        • Re: MOM-BACKUP-090901 action items closed - decision requiredIngo Strüwing22 Sep
          • Re: MOM-BACKUP-090901 action items closed - decision requiredRafal Somla23 Sep