I tried the solution to "Dissolving shapefiles but retain attribute fields" but my original shapefile (3000 rows in attribute table) has many duplicate values in the field that I want to retain so that the merge overruns the field width. Is there a way to merge only unique field values in the merged attribute field?
Take a read of the article HowTo: Identify duplicate field values.
From there do the following:
- set your definition query for the layer you made to
FIELD NAME = 0(this will identify all values that are unique.
- run your dissolve function on the data