MapServer on Oracle: Performance issue JOIN vs. LEFT JOIN

[Sebastian Schmitz]

Hi

we use Mapserver on Oracle Spatial 10gR2 using oraclespatial connection.
I want Mapserver to draw a geometry from a view. I experience that if 
the create view statement contains a LEFT JOIN statement, performance 
goes down enormously as opposed to a view created using a JOIN 
statement, where performance is fine. Data contained within the views 
will only vary a little bit between using LEFT JOIN and JOIN. I 
encounter the same behaviour when not using views, but plain SQL 
containing JOIN / LEFT JOIN statements.

How come? Workarounds in cases where I need a left join.....?

Cheers

Sebastian

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