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Hi list,<br>
<br>
I have come across an issue that is critical to the project I am
working on and wondered if it applies to all database drivers or
just the SQL Server 2008 one. <br>
<br>
I have logged the issue on GitHub at: <a
href="https://github.com/mapserver/mapserver/issues/5008">https://github.com/mapserver/mapserver/issues/5008</a><br>
<br>
I will try some tests over the weekend to see if the Postgres driver
works the same way, but there seems to be no way of guaranteeing
feature display order - even if all documentation suggests it can be
achieved in a database layer using "ORDER BY"<br>
Whilst for a low number of records the order seems ordered, with
150+ features I get different images returned each time by my WMS
service. No use of clustered indexes, partition statements etc. can
get around this as SQL result sets can only be guaranteed with an
ORDER BY in the outermost statement. <br>
<br>
I note that in <a
href="http://mapserver.org/fr/development/rfc/ms-rfc-105.html">http://mapserver.org/fr/development/rfc/ms-rfc-105.html</a>
there is a new function msLayerBuildSQLOrderBy() that allows sorting
to be done outside of the layer's DATA statement for WFS requests
with a SORTBY parameter. Maybe this could also be used by a new
LAYER "SORT" config keyword?<br>
<br>
I see the above is only implemented for a few drivers. The client
would be willing to fund adding this to the SQL Server driver if
there are any core devs interested in doing this. <br>
<br>
Regards,<br>
<br>
Seth<br>
<br>
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