[postgis-devel] [PostGIS] #593: [raster] Add a ST_BandIsNoData function

[PostGIS]

#593: [raster] Add a ST_BandIsNoData function
----------------------------+-----------------------------------------------
 Reporter:  pracine         |       Owner:  jorgearevalo 
     Type:  task            |      Status:  assigned     
 Priority:  medium          |   Milestone:  PostGIS 2.0.0
Component:  postgis raster  |     Version:  trunk        
 Keywords:                  |  
----------------------------+-----------------------------------------------

Comment(by jorgearevalo):

 Ok, summarizing:

 - The isnodata flag must be persistent, as the hasnodata flag is (it must
 be included in the WKB string)[[BR]]

 - Keeping the isnodata flag synchronized is too slow if we pretend to
 check it every time ST_SetValue / ST_SetBandNodataValue are called. We
 need a way to force synchronization. For example, a special version of
 ST_BandIsNoData function, with a boolean flag, to force this checking
 (doubt: if no band is specified, I guess band 1 is used by default, no all
 the raster bands). Other suggestions accepted.

-- 
Ticket URL: <http://trac.osgeo.org/postgis/ticket/593#comment:10>
PostGIS <http://trac.osgeo.org/postgis/>
The PostGIS Trac is used for bug, enhancement & task tracking, a user and developer wiki, and a view into the subversion code repository of PostGIS project.