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[CDO] Using the DB Mapping to populate queries [message #991334]

Tue, 18 December 2012 14:46

Christophe Bouhier

Messages: 937
Registered: July 2009

Senior Member

Hello,

Is there a way to access the DBStore MappingStrategy, so I can find out the column names in the DB? I know have to deal with column names which are sometimes case-incensitive, and sometime are CamelCased:

For example: Same code, different DB setup gives this:

MySQL setup 1:
Table name => metrics_MetricValueRange_metricValues_list

MySQL setup 2:
Table name => metrics_metricvaluerange_metricvalues_list

This would require to different SQL query text, to be succesful in both setups.

Additionally MySQL, likes to know the DB name to prefix the table. Can I fetch the DB/Schema name this from CDO somehow?

Thank You, Christophe

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Re: [CDO] Using the DB Mapping to populate queries [message #991374 is a reply to message #991334]

Tue, 18 December 2012 20:11

Eike Stepper

Messages: 6690
Registered: July 2009

Senior Member

Am 18.12.2012 15:46, schrieb Christophe Bouhier:
> Hello,
> Is there a way to access the DBStore MappingStrategy, so I can find out the column names in the DB? I know have to
> deal with column names which are sometimes case-incensitive, and sometime are CamelCased:
> For example: Same code, different DB setup gives this:
> MySQL setup 1: Table name => metrics_MetricValueRange_metricValues_list
>
>
> MySQL setup 2: Table name => metrics_metricvaluerange_metricvalues_list
I don't follow. Are you saying something in CDO causes these differences?

>
> This would require to different SQL query text, to be succesful in both setups.
I think something in the particular Mysql configurations causes case insensitive identifiers. In that case the case in
the queries wouldn't matter, either.

> Additionally MySQL, likes to know the DB name to prefix the table. Can I fetch the DB/Schema name this from CDO somehow?
All these informations should be accessible on the server side through IDBStore, IMappingStrategy, IClassMapping, etc.

If you need them at the client side, it would be possible to implement and contribute a custom IQueryHandler that
returns these mapping informations (or any other server information).

Cheers
/Eike

----
http://www.esc-net.de
http://thegordian.blogspot.com
http://twitter.com/eikestepper

Cheers
/Eike

----
http://www.esc-net.de
http://thegordian.blogspot.com
http://twitter.com/eikestepper

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Re: [CDO] Using the DB Mapping to populate queries [message #991929 is a reply to message #991374]

Thu, 20 December 2012 13:58

Christophe Bouhier

Messages: 937
Registered: July 2009

Senior Member

I am merely describing the differences. I am not pointing towards CDO regarding this.
I managed to work around this issue, but converting the queries to CamelCase table names, and this also works
on non-CamelCase column names. so it's fine.

Thanks for the pointer on IDBStore etc... I think I get the DB name from those API's. I need this info on the client and server.
(my CDO access code, is common to client and server). So an extended IQueryHandler implementation would be an option.

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