Creating a geodatabase and setting it to env.workspace

[EricEagle]

Any reason why this wouldn't be working?

import arcpy
import os

basedir = 'C:\\Temp'
gdb_name = 'TestGDB'
gdb = os.path.join(basedir, gdb_name)

if arcpy.Exists(gdb):
    arcpy.env.workspace = gdb
else:
    gdb = arcpy.CreateFileGDB_management(basedir, gdb_name)
    arcpy.env.workspace = gdb‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍

I must not be understanding how .Exists() resolves, for if the gdb already exists, it gives me:

arcgisscripting.ExecuteError: ERROR 000258: Output C:\Temp\TestGDB.gdb already exists

Failed to execute (CreateFileGDB)

If the gdb does not exist, it gives me:

RuntimeError: Object: Error in accessing environment <workspace>

[JoshuaBixby]

When creating the file geodatabase path for setting a workspace, you need to include the ".gdb" on the end, otherwise you are setting the workspace to a folder.

[IanMurray]

You are missing the file extension  in your gdb variable.  gdb_name needs the extension on it before you join the path.

[EricEagle]

Thanks Ian/Joshua,

When I include the .gdb extension (gdb_name = 'TestGDB.gdb') and the geodatabase exists, it completes.  When the geodatabase does not exist, it creates the TestGDB.gdb object, but still gives me the same runtime error.

[IanMurray · Accepted solution]

Can you check to make sure it creates the GDB?  I think its not creating it at all.

Make line 11 just:

arcpy.CreateFileGDB_management(basedir, gdb_name)

Right now instead of creating the actual gdb, you are setting a variable equal to it, which I'm not sure what that would do but it likely isn't creating it.

[EricEagle]

Thanks Ian.  It felt like I should be able to dump the method into a variable in one step like other methods to save a line of code, but regardless, it works now, thank you.

[IanMurray]

Hm it does create the GDB when you set it equal to a variable. I guess the issue with your script is the fact that arcpy.env.workspace is looking for a workspace as an input, whereas you were setting it equal to geoprocessing operation that creates the workspace. 

[JonathanQuinn]

Just to provide more insight, if you print the gdb variable, you'll get "<basedir>\<gdb_name>".  The OS separator between the out file path and FGDB name isn't escaped properly, as it's set to a backslash, which is why you see that runtime error when trying to use the gdb variable as is.  In one line, this worked:

gdb = str(arcpy.CreateFileGDB_management(outDir,outName)).replace("\\","/")

You can replace the single backslash, (escaped with a double backslash), with a forward slash.

[JoshuaBixby]

I am using ArcGIS 10.5, and Create File GDB returns properly escaped results:

>>> var = arcpy.CreateFileGDB_management(r'C:\tmp','test')
>>> var
<Result 'C:\\tmp\\test.gdb'>‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍
>>> arcpy.Exists(var)
True
>>> ‍‍‍‍‍‍

The double backslashes are perfectly valid, they don't have to be forward slashes.

[JonathanQuinn]

If you call on the variable without printing, it'll be correct as a Result object.  If you print the variable you'll see the backslash is not escaped:

>>> gdb = arcpy.CreateFileGDB_management("C:/Temp","blah.gdb")
>>> gdb
<Result 'C:/Temp\\blah.gdb'>
>>> print(gdb)
C:/Temp\blah.gdb
>>> arcpy.Exists(gdb)
True
>>> arcpy.env.workspace = gdb
Runtime error 
Traceback (most recent call last):
 File "<string>", line 1, in <module>
 File "c:\program files (x86)\arcgis\desktop10.5\arcpy\arcpy\geoprocessing\_base.py", line 541, in set_
 self[env] = val
 File "c:\program files (x86)\arcgis\desktop10.5\arcpy\arcpy\geoprocessing\_base.py", line 601, in __setitem__
 ret_ = setattr(self._gp, item, value)
RuntimeError: Object: Error in accessing environment <workspace>
>>> arcpy.env.workspace = str(gdb).replace("\\","/")
>>> arcpy.env.workspace
u'C:/Temp/blah.gdb'‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍

There seems to be different implementations of arcpy.Exists and arcpy.env.workspace, as the latter seems to look at the result as a string.