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<font face="Helvetica, Arial, sans-serif">Hi,<br>
<br>
did some buffer performance testing with a table that holds about 2100
multilinestrings (river network of europe).<br>
<br>
'select buffer(the_geom,5) from river;'<br>
<br>
takes about 7 seconds to execute, whereas<br>
</font><font face="Helvetica, Arial, sans-serif"><br>
'select buffer(the_geom,15000) from river' <br>
<br>
takes a couple of minutes...<br>
<br>
The 'river' table is not indexed, if this might be of importance ?!?<br>
<br>
'explain select....' <br>
<br>
shows similar output for both queries:<br>
<br>
QUERY PLAN<br>
-----------------------------------------------------------<br>
Seq Scan on river (cost=0.00..139.51 rows=2051 width=32)<br>
(1 row)<br>
<br>
<br>
What's the reason for the difference in execution time, depending on
the buffer size?<br>
Is there a way to speed up </font><font
face="Helvetica, Arial, sans-serif">execution time of </font><font
face="Helvetica, Arial, sans-serif">such queries??<br>
<br>
Best regards,<br>
alex.<br>
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