topic Delete Rows where value is Null in Python Questions

Delete Rows where value is Null

KarstenRank — Thu, 19 Jul 2012 18:54:23 GMT

Hello,

I have a table in a geodatabase where the value of a field is sometimes <Null>. How can I delete these rows?

Thanks for your help!

Best,
Karsten

Re: Delete Rows where value is Null

MathewCoyle — Fri, 10 Dec 2021 22:54:39 GMT

Off the top of my head I can think of two ways.

Option 1: Cursor

up_curs = arcpy.UpdateCursor(fc,"FIELD IS NULL")
for row in up_curs:
    if not row.getValue(FIELD):
        row.deleteRow(row)

Option 2: Select/Delete Features

arcpy.MakeFeatureLayer_management(fc,layer)
arcpy.SelectLayerByAttribute_management(layer,"FIELD IS NULL")
desc = arcpy.Describe(layer)

feat_count = int(arcpy.GetCount_management(parcel).getOutput(0))
feat_ids = desc.FIDSet

if feat_count > 0 and len(feat_ids) > 0:
    arcpy.DeleteFeatures_management(layer)

Note: I haven't tested either of these so make sure you do some trials in a test environment.

Re: Delete Rows where value is Null

KarstenRank — Fri, 10 Dec 2021 22:54:42 GMT

If I insert the field name "Liste", I get the error message <type 'exceptions.NameError'>: name 'Liste' is not defined.[ATTACH=CONFIG]16269[/ATTACH]

up_curs = arcpy.UpdateCursor(EingabeTabelle,"Liste IS NULL")
for row in up_curs:
    if not row.getValue(Liste):
        row.deleteRow(row)

Re: Delete Rows where value is Null

MarcinGasior — Fri, 20 Jul 2012 07:15:46 GMT

You have to provide valid SQL where clause and defined variable in getValue() function.
Here's an example:

import arcpy EingabeTabelle = r"C:\tmp\Test.gdb\YourTable" field = "Liste" whereClause = field + " IS NULL"  updCurs = arcpy.UpdateCursor(EingabeTabelle, whereClause) for row in updCurs:     if not row.getValue(field):         updCurs.deleteRow(row)

Re: Delete Rows where value is Null

KarstenRank — Sun, 22 Jul 2012 16:00:11 GMT

Thank you! This solved my probl

Best,
Karsten