[postgis-tickets] [PostGIS] #3011: ST_EstimatedExtent return a incorrect extent value

[PostGIS]

#3011: ST_EstimatedExtent return a incorrect extent value
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 Reporter:  rockyc              |       Owner:  pramsey
     Type:  defect              |      Status:  new    
 Priority:  medium              |   Milestone:         
Component:  postgis             |     Version:  2.1.x  
 Keywords:  ST_EstimatedExtent  |  
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Comment(by rockyc):

 Replying to [comment:1 pramsey]:
 > As the name indicates, the function is an estimate, generated by taking
 a sample. It's not necessarily going to be deterministic as you add and
 change records. How much does the estimate differ from the actual
 ST_Extent?

 Absolutely, we should expect this function to return a estimated value;

 But after adding a existing row, I expect the function returns the same
 value as before because no new geometry is added; at least, I expect the
 function returns a box which is bigger than the before one, because the
 box can not be smaller after more rows are added to the table,right?  but
 unfortunately, the returned box is much smaller than the previous one.

-- 
Ticket URL: <http://trac.osgeo.org/postgis/ticket/3011#comment:2>
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