Add Attribute Index (Data Management)


Adds an attribute index to an existing table, feature class, shapefile, or attributed relationship class.

Attribute indexes are used by ArcGIS to quickly locate records that match an attribute query.


  • Shapefiles and file geodatabase do not support multiple indexes, so additional fields will become part of a composite index (that is, an index created on multiple fields in a table).

  • Geodatabases have a new index added for each unique index name. If an index name already exists, it must be dropped before it can be updated.

  • For enterprise geodatabase data that is not registered as versioned, you can add both unique or non-unique indexes on GlobalID fields.

  • Unique and ascending indexes are not supported for shapefiles or file geodatabases. These parameters are ignored when the tool is executed on a shapefile or file geodatabase data.


AddIndex(in_table, fields, {index_name}, {unique}, {ascending})
ParameterExplanationData Type

The table containing the fields to be indexed.

Mosaic Layer; Raster Layer; Table View

The list of fields that will participate in the index. Any number of fields can be specified.


The name of the new index. An index name is necessary when adding an index to geodatabase feature classes and tables. For other types of input, the name is ignored.


Specifies whether the values in the index are unique.

  • NON_UNIQUEAll values in the index are not unique. This is the default.
  • UNIQUEAll values in the index are unique.

Specifies whether values are indexed in ascending order.

  • NON_ASCENDINGValues are not indexed in ascending order. This is the default.
  • ASCENDINGValues are indexed in ascending order.

Derived Output

NameExplanationData Type

The updated input table.

Table View; Raster Layer; Mosaic Layer

Code sample

AddIndex example 1 (Python window)

The following code demonstrates how to use the AddIndex function in a Python interactive window.

import arcpy
arcpy.env.workspace = "C:/data/input/indices.sde"
arcpy.AddIndex_management("gdb.USER1.lakes", ["NAME", "geocompID"], "NGIndex", "UNIQUE", "ASCENDING")
AddIndex example 2 (stand-alone script)

The following stand-alone script demonstrates how to create an attribute index for specified fields.

# Name:
# Description: Create an attribute Index for specified fields

# Import system modules
import arcpy
# Set a default workspace
arcpy.env.workspace = "c:/data"
# Create an attribute index for the few fields listed in command.
arcpy.AddIndex_management("counties.shp", ["NAME", "STATE_FIPS", "CNTY_FIPS"], "#", "NON_UNIQUE", "NON_ASCENDING")
arcpy.AddIndex_management("mexico.gdb/land/lakes", ["NAME", "geocompID"], "NGIndex", "NON_UNIQUE", "NON_ASCENDING")


Licensing information

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

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