[Mapserver-users] Multiple DSN Problem

[Frank Warmerdam]

D'cruz,Steven [Ontario] wrote:
> Hi there,
> 
>         I was wondering if anyone has any experience with executing 
> select statements using two different DSNs simultaneously.  For my work, 
> I require functionality similar to the following: "select a.* from 
> tablename1 a, tablename2 b where a.id=b.id and b.filter='t'" , where 
> tablename1 and tablename2 are from 2 DIFFERENT DSNs.  Both DSNs are to 
> be accessed via a realtime connection to a MS Access 2000 database from 
> a linux host via the FREETDS drivers.  I currently have both DSNs 
> working independently in 2 test layers (with no errors) using the 
> required fields.  Here's the .ovf file used for the selection queue from 
> the MS Access 2000 databases.

Steven,

Are the two tables you are interested in within the same MS-SQL database?
If so, you should be able to just do your join in a single SrcSQL statement.
Any SQL that the remote ODBC database supports can be in the SrcSQL
statement.

OGR SQL also has a built-in join syntax when you are working against
non-SQL enabled databases that allows accessing tables from different
datasources but that would be hard to make kick in when using stuff over
ODBC.

Best regards,

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