Checking to see if a Field Index Exists Using Python (geoprocessing 9.3).

Thu, 27 Jan 2011 15:31:48 -0600

NOTE: I have a post here that shows how to check if a field exists using arcpy in ArcGIS 10.0.

In developing a python script to reload a geodatabase, I wanted to create any necessary indexes.

No problem creating the index, for example:

gp.AddIndex_management(tablename, field, IndexName, "NON_UNIQUE", "NON_ASCENDING")

But before creating the index, I wanted to verify that it did not exist. I tried the ever-popular, exists but could not get it to work–either it does not detect indexes or I just never got the fully-qualified name for the index right (ArcSDE using a postgres datastore).

gp.Exists(mgs_c5ix_fullname)

I finally found this ArcGIS Desktop Help 9.3 – ListIndexes method from ESRI. Unfortunately, it doesn’t work-it did not like the ‘while’ loop construction. I’m guessing it worked in 9.2 and despite ESRI’s own warning about differences in 9.2 & 9.3, they did not update the sample code.

A key is to make sure you create a 9.3-version geoprocessing object and the following code can be used. The caveat that I need to include is that the code only checks one table, if the index is on a different table, it will give you a false-negative.

gp = arcgisscripting.create(9.3)

def indexExists(tablename,indexname):
 if not gp.Exists(tablename):
  return False

 indexList = gp.listindexes(tablename)

 for iIndex in indexList:
  if (iIndex.Name == indexname):
   return True

 return False

To call it, just pass the table and indexname you are looking for.

indexExists(tablename,indexname)

index on Node Dangles

Checking to see if a Field Index Exists Using Python (geoprocessing 9.3).