Friday, May 13, 2011

A Tip: Writing Queries Expression for Feature Class in Python

I see this question posted many times and it goes something like this: "Help, I've fallen and my SQL expression won't work!"  Well not exactly, but here is my tip.  Always use AddFieldDelimiters() if you don't know how to the field name should be formatted for a SQL query.


import arcpy

fc = "c:\temp\data.mdb/Stores"
fieldname = "ShopType"

# Create field name with the proper delimiters
field = arcpy.AddFieldDelimiters(fc, fieldname)
# Create a search cursor using an SQL expression
rows = arcpy.SearchCursor(fc, field + " = 2")
for row in rows:
     #do something
del rows