Indexing long text fields failing using arcpy AddIndex?

Question

Arcpy AddIndex_management won't index long text fields, is there a workaround?

I tried:

arcpy.AddIndex_management(r'C:\workspace\foo.dbf', "Text")

and got the error:

Runtime error  Traceback (most recent call last):   File "<string>", line 1, in <module>   
  File "c:\program files (x86)\arcgis\desktop10.3\arcpy\arcpy\management.py", line 5993, in AddIndex     
  raise e ExecuteError: 
  ERROR 999999: Error executing function. 
  Attribute indexes cannot be created for fields with a length that is greater than 80. 
Failed to execute (AddIndex).

I have also tried this with shapefiles as well as dbf's with the same error. I need to index a text field in order to perform a JoinField() more quickly with arcpy.

Is there a work around to do this that doesn't involve shortening text fields?

I haven't seen a reason not to index fields longer than 80 characters; especially since the text fields I'm indexing have been calculated and are therefore not very prone to typos. For example, if you had a series of field of species names and you wanted to join that to a table containing descriptions of those species, you would be joining on a potentially long text string.

Answer 1

If you CAN edit the length of text fields the answer is as follows:

arcpy.AddField(r'C:\workspace\foo.dbf', "shortText", "#", "#", 75, "#", "#", "#", "#")
with arcpy.da.updateCursor(r'C:\workspace\foo.dbf', ["Text", "shortText"]) as cursor:
    for row in cursor:
        row[1] = row[0]
        cursor.updateCursor(row)
arcpy.AddIndex_management(r'C:\workspace\foo.dbf', "shortText")

and then perform your join on "shortText"