Make Feature Layer (Data Management)

Summary

Creates a feature layer from an input feature class or layer file. The layer that is created by the tool is temporary and will not persist after the session ends unless the layer is saved to disk or the map document is saved.

Usage

• The temporary feature layer can be saved as a layer file using the Save To Layer File tool or can be saved as a new feature class using the Copy Features tool.

• Complex feature classes, such as annotation and dimensions, are not supported by this tool.

• If an SQL expression is used but returns nothing, the output will be empty.

• The field names will be validated by specifying an input workspace. Thus, if the input is a geodatabase feature class, and the output workspace is a folder, the field names may be truncated, since shapefile attributes can only have names of ten characters or less.

• A split policy can be set by using the Field Info control's Ratio option. The split policy comes into effect any time the feature layer is being used as an input to a tool and a geometry of the input feature layer is split during processing. When the split geometry is sent to the output, a ratio of the input attribute value is calculated for the output attribute value. When Ratio is enabled, whenever a feature in an overlay operation is split, the attributes of the resulting features are a ratio of the attribute value of the input feature. The output value is based on the ratio in which the input feature geometry was divided. For example, if the input geometry was divided equally, each new feature's attribute value is assigned one-half of the value of the input feature's attribute value. The Ratio policy only applies to numeric field types.

  The default is none (unchecked). This means the attribute of the two resulting features takes on a copy of the original object's attribute value.

  Caution:

  Geoprocessing tools do not honor geodatabase feature class or table field split policies.

• When using ModelBuilder to create a tool, you need to ensure that the input data variable to this tool is not flagged as intermediate. If the input is flagged as intermediate, it will be deleted after the model is run from its dialog and the output layer will not be added to the display.

• In a model, the output variable of Make Feature Layer tool can be assigned a layer file from which to apply symbology to the layer being created. When the layer being created is returned as a model or script tool output parameter to a map, the symbology from the layer file is preserved but the label properties are not. However, if the layer created by Make Feature Layer (in a model) is saved as permanent data (feature class or shapefile), and that permanent data is returned to the map as an output parameter, the label properties from the layer file are correctly applied.

Syntax

MakeFeatureLayer(in_features, out_layer, {where_clause}, {workspace}, {field_info})

Parameter	Explanation	Data Type
in_features	The input feature class or layer from which to make the new layer. Complex feature classes, such as annotation and dimensions, are not valid inputs to this tool.	Feature Layer
out_layer	The name of the feature layer to be created. The newly created layer can be used as input to any geoprocessing tool that accepts a feature layer as input.	Feature Layer
where_clause (Optional)	An SQL expression used to select a subset of features. For more information on SQL syntax see the help topic SQL reference for elements used in query expressions.	SQL Expression
workspace (Optional)	The input workspace used to validate the field names. If the input is a geodatabase table and the output workspace is a dBASE table, the field names may be truncated, since dBASE fields can only have names of ten characters or less.	Workspace; Feature Dataset
field_info (Optional)	Can be used to review and hide a subset of fields in the output layer. A split policy can be specified. See the usages for more information.	Field Info

Code sample

MakeFeatureLayer example 1 (Python window)

The following Python window script demonstrates how to use the MakeFeatureLayer function in immediate mode.

import arcpy

arcpy.env.workspace = "C:/data/input"
arcpy.MakeFeatureLayer_management("parcels.shp", "parcels_lyr")

MakeFeatureLayer example 2 (stand-alone script)

The following stand-alone script demonstrates how to use MakeFeatureLayer to create a layer that can be used by SelectLayerByLocation and SelectLayerByAttribute tools.

# Name: ExtractFeaturesByLocationAndAttribute.py
# Description:  Extracts features to a new feature class based on a location and an attribute query.

# Import system modules
import arcpy

# Set overwrite option
arcpy.env.overwriteOutput = True

# Put in error trapping in case an error occurs when running tool
try:

   # Make a layer from the feature class
   arcpy.MakeFeatureLayer_management("C:/data/mexico.gdb/cities","cities_lyr")

   # Select all cities that overlap the chihuahua polygon
   arcpy.SelectLayerByLocation_management("cities_lyr", "INTERSECT", "c:/data/mexico.gdb/chihuahua", "", "NEW_SELECTION")

   # Within the selection (done above) further select only those cities that have a population >10,000
   arcpy.SelectLayerByAttribute_management("cities_lyr", "SUBSET_SELECTION", "POPULATION > 10000")

   # Write the selected features to a new featureclass
   arcpy.CopyFeatures_management("cities_lyr", "c:/data/mexico.gdb/chihuahua_10000plus")

except:
   print(arcpy.GetMessages())

Environments

Current Workspace

Licensing information

• Basic: Yes
• Standard: Yes
• Advanced: Yes