I'm having trouble with the SelectLayerByAttribute_management() tool. Although it produces no errors or whatsoever, I get an empty selection.
This is the code I am using in my standalone script. I've run it down to the part that's causing trouble and added lots of checks
This evaluates to:
As you can see, layer exists, feature class exists, field exists, there are features in the featureclass, and on my word, there are also features with the mentioned attributes.
Performing a select by attributes from the arcmap menu or arcmap attribute table view, using the exact same sql phrases does result in a selection. Copying the lines one by one to the arccatalog or arcmap script window does not.
This is the code I am using in my standalone script. I've run it down to the part that's causing trouble and added lots of checks
Code:
import arcpy
database = 'D:/Menno/openhabitat/Keillour/HabitatSDM/Habitats.gdb'
fc = database + '/SurveyData/HabitatSiteArea'
subs = ['504S34','504S35']
sql = """ "PolygonNo" = '%s' """
lyr = 'lyr'
# create empty layer to add features to
arcpy.MakeFeatureLayer_management(fc,lyr,sql % '')
print 'layer exists:', arcpy.Exists(lyr)
print 'features in lyr:', arcpy.GetCount_management('lyr').getOutput(0)
print 'featureclass exists:', arcpy.Exists(fc)
print 'features in feature class:', arcpy.GetCount_management(fc).getOutput(0)
l = arcpy.ListFields(fc)
m = []
for a in l:
m = m + [a.name]
print 'field exists in featureclass:', 'PolygonNo' in m
# loop along PolygonNos and add each feature to the selection layer
for f in subs:
print 'PolygonNo:', f
print 'Sql:', sql % f
arcpy.SelectLayerByAttribute_management(lyr,'ADD_TO_SELECTION', sql % f)
print 'Features in lyr after select:', arcpy.GetCount_management(lyr).getOutput(0)
##arcpy.DeleteFeatures_management(lyr)
print 'End'Code:
layer exists: True
features in lyr: 0
featureclass exists: True
features in feature class: 60
field exists in featureclass: True
PolygonNo: 504S34
Sql: "PolygonNo" = '504S34'
Features in lyr after select: 0
PolygonNo: 504S35
Sql: "PolygonNo" = '504S35'
Features in lyr after select: 0
EndPerforming a select by attributes from the arcmap menu or arcmap attribute table view, using the exact same sql phrases does result in a selection. Copying the lines one by one to the arccatalog or arcmap script window does not.