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<DIV class=section id=list-archives>hi,</DIV>
<DIV class=section>i have OSGB36 data in postgre, srid 27700. what i want to do is to calculate the extent on basis of the distance from a given point. i have geom of type geometry in the table, from which to calculate extent. i have tried the funtions Distance(geom,geom)<50, but it is too slow, as it uses no index. i have calculated the point from the polygon by function Centroid(geom), from where the other distances have to be calculated, but i think its not working properly, as i am also testing it with the mapserver map and map saclebar, they are not matching exactly. i mean the scalebar is not showing 100 meter but instead showing 192 meters.</DIV>
<DIV class=section>the main isuue is of the time the distance query is taking.</DIV>
<DIV class=section>is there any why else to do this quickly.</DIV>
<DIV class=section>thanks</DIV></DIV></div><br>
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