<font size=2 face="sans-serif">I am querying an Oracle Spatial table.
I am restricting the query using an attribute in the table (road
type). In examining the query sent to Oracle, it seems to query by
attribute first, then by spatial envelope. For datasets that only
return a few features in the attribute query, this seems fairly efficient.
However, for datasets that return many features in the attribute
query that lie over a large spatial area, it would seem more efficient
to limit by spatial envelope first, then by attributes, especially if the
query area is relatively small compared to the spatial extent of the dataset.
Can the user be allowed to set the spatial/attribute query order?</font>
<br>
<br><font size=2 face="sans-serif">Example query - attribute query is executed
first, then spatial. For small spatial areas, the query might be
faster if the spatial filter were executed first.</font>
<br>
<br><font size=2 face="sans-serif">DATA "SHAPE FROM (SELECT SHAPE
FROM ROAD_TABLE WHERE DESG IN ('CST','CRD')) USING SRID 8307"</font>
<br><font size=2 face="sans-serif"><br>
Stuart Harlan<br>
Senior Information Systems Technologist<br>
GIS Web Services<br>
Transportation Planning Division<br>
Missouri Department of Transportation</font>