Build Overviews (Data Management)


Defines and generates overviews on a mosaic dataset.


  • This tool will honor the default mosaic dataset settings, not the properties set on a mosaic dataset layer. For instance, the tool will not accept layer property changes such as band count, mosaic method, extent, or query—these properties will be determined by the mosaic dataset and default properties of the mosaic dataset.

  • You must check on Define missing overview tiles, Generate overviews, or both.

  • The first overview level is created on the full resolution of the mosaic dataset. Each subsequent level is built on the last overview level that was generated.

  • If you need more control over the definition of the overviews, use the Define Overviews tool first.

  • By default, the overviews generated for mosaic datasets in a file geodatabase are stored in a folder <gdbname>.Overviews in the same location where the geodatabase containing the mosaic dataset exists. The overviews generated for mosaic datasets on the enterprise geodatabase are stored within the geodatabase containing the mosaic dataset. These locations can be changed by first using the Define Overviews tool and specifying a location.

  • You cannot build overviews for a referenced mosaic dataset.


BuildOverviews(in_mosaic_dataset, {where_clause}, {define_missing_tiles}, {generate_overviews}, {generate_missing_images}, {regenerate_stale_images})
ParameterExplanationData Type

The mosaic dataset where you want to build overviews.

Mosaic Layer

An SQL statement to select specific rasters within the mosaic dataset. The selected rasters will have their overview built.

SQL Expression

Identify where overviews are needed and define them.

  • DEFINE_MISSING_TILESAutomatically identify where overviews are needed and define them. This is the default.
  • NO_DEFINE_MISSING_TILES Do not define new overviews.

Generate all overviews that need to be created or re-created. This includes missing overviews and stale overviews.

  • GENERATE_OVERVIEWSGenerate all overviews, including those that already exist. This is the default.
  • NO_GENERATE_OVERVIEWSGenerate only the overviews that have been defined but not yet generated.

Use if overviews have been defined but not generated.

  • GENERATE_MISSING_IMAGESGenerate overviews that have been defined but not generated. This is the default.
  • IGNORE_MISSING_IMAGES Do not generate overviews that have been defined but not generated.

Overviews become stale when you change the underlying raster datasets or modify their properties.

  • REGENERATE_STALE_IMAGESIdentify and regenerate stale overviews. This is the default.
  • IGNORE_STALE_IMAGES Do not regenerate stale overviews.

Derived Output

NameExplanationData Type

The updated mosaic dataset.

Mosaic Layer

Code sample

BuildOverviews example 1 (Python window)

This is a Python sample for BuildOverviews.

import arcpy
     "C:/Workspace/Overviews.gdb/md", "OBJECTID<5", "DEFINE_MISSING_TILES", 
BuildOverviews example 2 (stand-alone script)

This is a Python script sample for BuildOverviews.

# Define Overviews for selected items only

import arcpy
arcpy.env.workspace = "C:/Workspace"

arcpy.BuildOverviews_management("Overviews.gdb/md", "OBJECTID<5", 
                                "NO_GENERATE_OVERVIEWS", "#", "#")

Licensing information

  • Basic: No
  • Standard: Yes
  • Advanced: Yes

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