I have ~600 lyr files that reference a table on an SDE database that has about 20,000,000 records. Some of these *lyr files have an incorrect definition query applied or is missing the query entirely.

I think I'm looking for a way to create a table with the Lyr file name and it's definition query, but I'm not sure if that's something I can do in python or model builder. Can anyone pt me in the right direction?


The arcpy.mapping module makes it pretty easy if you're comfortable doing a little Python coding. Here's the basic outline:

At the beginning of your Python script, get the list of .lyr files (using glob.glob("*.lyr"), for example).

Then for each file, call arcpy.mapping.ListLayers(filename), passing it the filename of your .lyr file. This returns a list of Layer objects.

Each of these Layer objects has a definitionQuery property that you could print or write to a file.

I imagine the code would be something like this (though I haven't actually tried to run this):

import glob
import arcpy
import arcpy.mapping
filenames = glob.glob("C:\\path\\to\\layer\\files\\*.lyr");
for filename in filenames:
    layers = arcpy.mapping.ListLayers(filename)
    for layer in layers:
        print filename + ',' + layer.longName + ',' + layer.definitionQuery

And you should get output like this:

C:\path\to\layer\files\foo.lyr,Some Layer Name,WHERE foo='xyz'
C:\path\to\layer\files\var.lyr,Another Layer Name,WHERE foo='abc'

This function (inventory_layers_and_mxds) will create a new table and populate it with definition queries

import os

import arcpy

def inventory_layers_and_mxds(out_table, folder_to_inventory, mxds=True, lyrs=True):
    # Set up inventory table
    print [os.path.dirname(out_table),
    arcpy.management.AddField(out_table, "mapdocument", "TEXT",
    arcpy.management.AddField(out_table, "layername", "TEXT",
    arcpy.management.AddField(out_table, "definitionquery", "TEXT",

    # open cursor, loop over directory looking for MXDs
    with arcpy.da.InsertCursor(out_table,
                                "definitionquery"]) as inv_cursor:
        # Spider through folder
        for foldername, subdirectories, files in os.walk(folder_to_inventory):
            for filename in files:
                file_path = os.path.join(foldername, filename)
                item = None
                # Is file an MXD and are we looking at map docs?
                if os.path.splitext(filename)[1].lower() == ".mxd" and mxds:
                    mxd = arcpy.mapping.MapDocument(file_path)
                    item = mxd 
                # Is file a LYR and are we looking at layers?
                if os.path.splitext(filename)[1].lower() == ".lyr" and lyrs:
                    lyr = arcpy.mapping.Layer(file_path)
                    item = lyr
                if item is not None:
                    # Now loop over layers
                    for layer in arcpy.mapping.ListLayers(item):
                        # Only insert row if it does a definition query
                        # (ignore group layers etc)
                        if layer.supports("DEFINITIONQUERY"):
                            inv_cursor.insertRow([file_path, layer.longName,

With the ArcPy Mapping module you can read or write a Layers definitionQuery. Here is a blog post.
Working with a Definition Query, ArcPy and Python

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