spatial - SQL Server 2008 Geometry.STBuffer(…) really slow -

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i’ve got basic sql query looks like:

select top 1 [geom].stbuffer(500) [db].[dbo].[boundaries]

which essential takes map boundary database , buffers 500m. problem i’m having it’s incredibly slow , server runs out of memory! i’m sure must wrong simple operation in gis program takes seconds run, whereas runs around minute before giving up.

the boundary complicated, shouldn’t complicated cause server run out of memory, i’m sure of that.

if reduce buffer distance 100m, runs , completes within around 14 seconds, still slow useful in realtime.

any idea why might slow, , tips how can speed up?

thanks,

this known limitation stbuffer in sql server 2008 - prone being slow , potentially running out of memory when distance parameter larger diameter of object , object has more 1000 points. there connect item issue , fixed in sql server denali.

as workaround, can try running reduce on object before invoking buffer lower complexity, , using bufferwithtolerance method pass in higher tolerance result in less complex result.


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