Raster Dataset Change/Update NoData Value Property

Question

So we have a raster in an SDE Oracle database... the "NoData Value" property is set to 256 and should be set to 255... WHY can I not find a way to change this property value? I DO NOT want to recalculate all the 255 pixels in the map (this is a huge raster), I simply want to change the "NoData Value" property. The closest thing I have found is to have our DBA run: sderaster -o update -l -v -a 255 But not real sure for one if this does what I want or if it recalculates all the pixels, and two what to put for and ... Any help or ideas would be great! Thanks a lot!

StevenHoek · Answer

Hi there,
Whilst working with a raster of type GRID, I encountered the same problem. The NoData value of my raster was not set correctly. Even copying the raster with the tool "copy raster" from the toolbox did not work. I finally succeeded by following the advice from ArcGIS Desktop Help. I found the solution by selecting the item "Spatial Analyst toolbar, reclassifying data with" and then saw this at the bottom of the right page: "Setting specific values to NoData". The advice I found there, led me to the solution. HTH
Regards ...Greetings,

Yes, you cannot simply change the nodata value of a raster dataset, either in SDE or on a file based raster dataset. The only way to change the nodata value is to rewrite the dataset and change the nodata value in the process (e.g. in copy raster). 
Simply changing the nodata value, especially in SDE, might create issues, so be careful changing something through the DB rather than ArcObjects.

Robert

RobertBerger · Answer

Greetings,

Yes, you cannot simply change the nodata value of a raster dataset, either in SDE or on a file based raster dataset. The only way to change the nodata value is to rewrite the dataset and change the nodata value in the process (e.g. in copy raster). 
Simply changing the nodata value, especially in SDE, might create issues, so be careful changing something through the DB rather than ArcObjects.

Robert