Re: back-sql mysql innodb

[Frederik Bosch <frederik.bosch@gmail.com>]

Thanks p.. I did some more testing and you are right. It is a RDBMS 
problem. This is what I found (tested with iSQL and directly on the RDBMS).

In chronological order:

1. SET autocommit=0
2. SELECT @@autocommit -> result: 0, it is turned off

This is standard slapd/back-sql config.

3. SELECT * FROM ldap_entries -> 10 results
4. Now I change the data directly using a different connection and other 
GUI. I add a record (and commit it).
5. SELECT * FROM ldap_entries -> 10 results

The latter result surprised me. So if data is changed by another 
connection, it will not be refresh data on other connections.

6. COMMIT
7. SELECT * FROM ldap_entries -> 11 results

So, in order to refresh data, slapd has to prepend every read operation 
with a COMMIT. This is not logical, is it?

So, I believe adding a configuration option, for people who want to use 
back-sql with MySQL/InnoDB, could be a handy solution. Where can I add 
this feature request?

Regards,
Frederik



On 07/28/2010 03:01 PM, masarati@aero.polimi.it wrote:
> > Problem solved. I had to comment a line in sql_wrap.c:
> >
> > /*
> >    * TimesTen : Turn off autocommit.  We must explicitly
> >    * commit any transactions.
> >    */
> > SQLSetConnectOption( *dbhp, SQL_AUTOCOMMIT, SQL_AUTOCOMMIT_OFF );
> >
> > This last line actually prevents slapd from updating resultsets (which
> > are committed) in InnoDB.
>
> I believe this is not correct; we need autocommit to be off since
> operations that need a commit explicitly do it.  I think the problem is in
> the RDBMS you're using, since other RDBMSes always worked as intended.
>
> > Perhaps autocommit should be enabled by default, but the user should be
> > able to disable it through a configuration option in slapd.conf. Should
> > I file a request or bug for this?
>
> Feel free.  Configuration options that improve interoperation are always
> welcome, pending my comment above.
>
> p.