topic Re: Looking for proper syntax for SQL expression in Python to select features by attribute in Python Snippets Questions

Looking for proper syntax for SQL expression in Python to select features by attribute

deleted-user-AOHsGDn8SRw7 — Wed, 19 Apr 2017 16:36:22 GMT

I am trying to create a simple code that will select features in a shapefile based on the query {anything within the ATTRIBUTE field that starts with the letter 'P'}. Here the problematic line:

arcpy.SelectLayerByAttribute_management("NJ_Wetlands", "NEW_SELECTION", """"ATTRIBUTE" LIKE P%""")

I know I could do this simply in the toolbox GUI, but I'm trying to learn arcpy. I'm obviously doing something wrong, and it shouldn't be very complicated. I get the error:

Runtime error Traceback (most recent call last): File "<string>", line 1, in <module> File "c:\program files (x86)\arcgis\desktop10.5\arcpy\arcpy\management.py", line 7713, in SelectLayerByAttribute raise e ExecuteError: ERROR 000358: Invalid expression Failed to execute (SelectLayerByAttribute).

I've already tried searching through various forums and some help guides on Esri.com, but no dice. I guess I need this help to be explained very explicitly, otherwise I am lost.

Re: Looking for proper syntax for SQL expression in Python to select features by attribute

JoshuaBixby — Wed, 19 Apr 2017 16:49:05 GMT

How about:

arcpy.SelectLayerByAttribute_management("NJ_Wetlands", "NEW_SELECTION", "ATTRIBUTE LIKE 'P%'")‍

Since you are wanting to learn Python, I encourage you to read String literals section of the Lexical analysis Python documentation.

Re: Looking for proper syntax for SQL expression in Python to select features by attribute

deleted-user-AOHsGDn8SRw7 — Wed, 19 Apr 2017 21:51:21 GMT

Thank you, it worked like a charm!

Re: Looking for proper syntax for SQL expression in Python to select features by attribute

JoshuaBixby — Thu, 20 Apr 2017 13:40:27 GMT

Please mark an answer correct to close out the question, thanks.