I have raster dataset for rainfall but it does not have an attribute table.
How can I create tabular data using the same raster file and the join back again to it?
Software used is ArcMap 10.1.
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You could use the Build Raster Attribute Table (Data management) tool. Note that the raster must have a single band and the pixel values must be integer type (not float or double) to have an attribute table.
I found this problem occuring mainly when handling raster data with floating point data. The straight forward approach (in the ArcMap Toolbox' sense of way):
ArcToolbox > Spatial Analyst Tools > Map Algebra > Raster Calculator
Multiply your raster by 10**X with X corresponding the maximum decimal places contained. The new raster should now be free of digits, although still being a floating pixel value raster.
ArcToolbox > Data Management Tools > Raster > Raster Dataset > Copy Raster
In the Pixel Value drop-down menu select the Pixel Type suiting your data.
Now that you have a non-float raster (and ArcMap surely loves these) create an attribute table:
ArcToolbox > Data Management Tools > Raster > Raster Properties > Build Raster Attribute Table
Open the attribute table, add a field and use Field Calculator to get your old pixel values back - by calculating "Your Value= 1 / 10**X"
You can use Int tool to convert floating point to integer raster and after you process that, the attribute table will appear.