Avoiding errors when adding rows to blank table using ArcPy?

[DavidSouth2]

I am having problems when using ArcPy with ArcGIS Desktop to add in a set number of rows into a .dbf table.

What should I do to prevent these errors?

Here is a sample code that gives me errors:

##########setup###########
import arcpy, os
from arcpy import env


##########parameters##########

ws = r'C:\Users\ddsouth\Documents\Python_tests'
env.workspace = ws

newFile = "adding_table_rows_test_5"
newFileFull = os.path.join(ws, newFile) + ".dbf"

###########code###############

#create the table
arcpy.CreateTable_management(ws, newFile)
arcpy.AddField_management(newFileFull, "RouteName", "TEXT", "", "", 15)
arcpy.AddField_management(newFileFull, "DepotName", "TEXT", "", "", 15)

#edit the table
cursor = arcpy.da.InsertCursor(newFile, ["ROUTENAME"])

for q in range (0,10):
 cursor.insertRow((str(1),))
del cursor

print "Completed."

The creation of the table goes fine the first time, then when it comes to the edit portion I get the following error message:

Runtime error Traceback (most recent call last):  
File "<string>", line 26, in <module>SystemError: error return without exception set

Then if I run the program again, I get a different error, this time during the creation of the table, even if I have the "Overwrite the outputs of geoprocessing operations" option selected:

Runtime error  Traceback (most recent call last):   
File "<string>", line 18, in <module>   
File "c:\program files (x86)\arcgis\desktop10.4\arcpy\arcpy\management.py", 
line 15715, in CreateTable     
raise e ExecuteError: ERROR 001143: Background server threw an exception.

I also noticed that while the tables I created appear in ArcCatalog, they do not appear in Windows Explorer, there is only a LOCK file while ArcMap is open.

What should be done? Thank you!

[JoshuaBixby]

Cross-posted to StackExchange:  Avoiding errors when adding rows to blank table using ArcPy?

Since this is a question, it is best to mark it as a question instead of a discussion.

[DavidSouth2]

Thanks, I will remember this for next time. I am still getting used to how this site works.

[JoshuaBixby]

Do you mean to be working with Info or dBASE tables?  Your code as written is creating an Info table and trying to insert records into it.  I am surprised the Add Field calls aren't generating errors.

[curtvprice]

I noticed you opened the cursor on newFile, not newFileFull, which is missing the .dbf extension. Mr Bixby is right on that a table path in a folder with no .dbf tacked on is interpreted as an INFO table path. Good old INFO. A humble personal financial database put into service mapping the world.

I really like to make table views both for performance reasons when I run multiple tools on a single input (speedier validation) but also this can insulate your from path specification errors like that.

#create the table
tbl = arcpy.CreateTable_management(ws, newFile)
tv = arcpy.MakeTableView_management(tbl, "tv")
arcpy.AddField_management(tv, "RouteName", "TEXT", "", "", 15)
arcpy.AddField_management(tv, "DepotName", "TEXT", "", "", 15)

#edit the table
cursor = arcpy.da.InsertCursor(tv, ["ROUTENAME"])

...

# clean up tv
arcpy.Delete_management(tv)
‍‍‍‍‍‍‍‍‍‍‍‍‍

[NeilAyres]

Sorry for hijacking this thread....

Back in the day, my bookshelf contained a photocopied version of "Understanding Info" by Henco software.

It was my bible in those days.

[curtvprice]

PROGRAM SECTION EVEN and RELATE FILL ORDERED... those were the days!

AML forever, brother!

[DavidSouth2]

Hello Curtis,

Thank you for the response. I have changed my code to look like this:

##########setup###########
import arcpy, os
from arcpy import env

##########parameters##########

ws = r'C:\Users\ddsouth\Documents\Python_tests'
env.workspace = ws

newFile = "adding_table_rows_test_3"

###########code###############
#create the table
tbl = arcpy.CreateTable_management(ws, newFile)
tv = arcpy.MakeTableView_management(tbl, "tv")
arcpy.AddField_management(tv, "RouteName", "TEXT", "", "", 15)
arcpy.AddField_management(tv, "DepotName", "TEXT", "", "", 15)

#edit the table
cursor = arcpy.da.InsertCursor(tv, ["ROUTENAME"])

for q in range (0,10):
    cursor.insertRow((str(1),))
del cursor

#clean up tv
arcpy.Delete_management(tv)‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍

print "Completed."

Yet I still get the error on the "cursor.insertRow((str(1),))" line:

Runtime error

...

SystemError: error return without exception set

Is there a way to fix this? I really appreciate the help.

[JoshuaBixby]

Do you mean to be working with Info or dBASE tables?  Your code as written is still creating an Info table and trying to insert records into it.  Before I get into explaining Info-related issues with cursors, I want to make sure you want to be working with Info tables.  Do you have to be working with Info tables or would dBASE work as well?

[curtvprice · Accepted solution]

Just to be clear, the change you need is to set the output pathname with a #dbf extension. This is only necessary when the output workspace (ws) is a folder, with no extension there is an assumption you have created an info folder with the CreateWorkspace command or by running a tool that creates an INFO directory. This is historical compatibility; these days you should avoid INFO table format unless you have no way around it (for example, coverage and Esri grid formats).

newFile = "adding_table_rows_test_3.dbf"

I also would not use this:

cursor.insertRow((str(1),))

but instead, this. (I just like lists over tuples, you can simply do more with them.)

cursor.insertRow(["1"])