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extension (for Explores)

This page refers to the extension parameter that is part of an Explore.

extension can also be used as part of a view, as described on the extension (for views) parameter documentation page.

extension can also be used as part of a LookML dashboard, as described on Dashboard parameters documentation page.


explore: explore_name {
  extension: required
Default Value

The value “required”


The extension: required parameter flags an Explore as requiring extension, which means that the Explore cannot be used on its own. The contents and settings of the Explore will only be used when the Explore is extended using the extends parameter in another Explore.

An Explore with extension: required is not visible to users on its own; it is intended only to act as a starting point to be extended by other Explores.

The extension parameter accepts only the value required. If you don’t want to require extension for an Explore, leave out the extension parameter entirely.

An Explore with extension: required cannot be used as an explore_source for a data test. The LookML Validator will generate an error that the explore_source cannot be found.

See Reusing Code with Extends for more information on using extends for LookML objects.


This basic_order_fields Explore has the extension: required parameter, so the Explore itself will not be visible to users:

explore: basic_order_fields { extension: required }

To make use of the basic_order_fields Explore, we can create another Explore that extends it, like this:

explore: marketing_order_fields { extends: [basic_order_fields] }

It may be tempting to turn on hidden to hide Basic Order Fields, but remember that such a setting is going to be inherited by any Explore that is based on Basic Order Fields. In this particular example, Marketing Order Fields would be hidden as well if you turned on hidden.