topic Re: Add a definition Query with python in Python Questions

Add a definition Query with python

PeterVersteeg — Fri, 10 Dec 2021 20:05:42 GMT

I want to add a difinition query with python so far i have this

import arcpy  
  
mxd = arcpy.mapping.MapDocument(r"Y:\TRUTTA\Trutta_new\TruttaMaps\test.mxd")


for lyr in arcpy.mapping.ListLayers(mxd, "*"):
    if lyr.name == "chimney_p":
        lyr.definitionQuery = """"Trutta_Map" = '19A4'"""

In my pythonWin it seems to work BUT the query in my shape did not get the new query.

anyone know why that is ?

Re: Add a definition Query with python

DanPatterson_Retired — Thu, 19 Feb 2015 08:19:31 GMT

The query may have work, but it isn't going to show up unless you are running the script against "CURRENT" See example 2 in this link

Re: Add a definition Query with python

OwainCatton — Fri, 10 Dec 2021 20:05:45 GMT

Hi Peter,

You are missing just the last step, saving the MXD when you have finished editing the layers.

So your code should read.

import arcpy

mxd = arcpy.mapping.MapDocument(r"Y:\TRUTTA\Trutta_new\TruttaMaps\test.mxd")

for lyr in arcpy.mapping.ListLayers(mxd, "*"):
     if lyr.name == "chimney_p":
          lyr.definitionQuery = """"Trutta_Map" = '19A4'"""

mxd.save()

Hope that helps,

Owain

Re: Add a definition Query with python

PeterVersteeg — Thu, 19 Feb 2015 13:42:43 GMT

thank you Dan this gives my samething to read in the train and learn more about the mapping.

gr Peter

Re: Add a definition Query with python

PeterVersteeg — Thu, 19 Feb 2015 13:50:07 GMT

Thank you Owain,

That did the trick. Did not
know about the save part. My fist try was a error because I had the mxd open in
arcmap. In other scripts a had lock errors. Same scripts work even if the mxd
is open. What are the rules for this ? where can I read about it ?

Greetings Peter

Re: Add a definition Query with python

OwainCatton — Thu, 19 Feb 2015 13:59:01 GMT

Afternoon Peter,

As Dan mentioned above, the use of CURRENT instead of a file path would mean that the Python script will edit the current ArcMap session, where as if you specify the file path the Python script will open a new session, hence the locks errors your were getting as you had the MXD already open.

MapDocument Example 1
If you have a the MXD open in ArcMap and want to run a script on its contents use CURRENT
MapDocument Example 2
If you want to run the script independently you specifiy te full File Path

Owain