The SQL To Run Before Read is not for that, but your Reader feature type(s) will have a WHERE clause option which you can use.

The SQL To Run Before Read is for any other queries you'd like to run before the workspace starts reading from that database.

The "Esri Geodatabase (File Geodb)" reader requires the ArcGIS license and I do not have the ArcGIS license. I am using "Esri Geodatabase (File Geodb Open API)" reader and the WHERE clause is disabled. I was hoping the "SQL To Run Before Read" would be a workaround, that seems not to be the case.

The WHERE clause is only disabled in the FeatureReader. When I add a classic Esri Geodatabase (File Geodb Open API) it just works as expected.

In the Navigator window, go to Feature Types, select feature type, parameters, format, WHERE Clause.

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The Esri Geodatabase (File Geodb Open API) reader only supports WHERE on Feature Types, not at the reader level. Most other database readers (including Esri Geodatabase (File Geodb)) support a WHERE at both the reader level (not that useful) and on the Feature Types.

The FeatureReader currently only supports the WHERE at the reader level, not on individual feature types. Hence WHERE isn't available for the Esri Geodatabase (File Geodb Open API) reader in the FeatureReader but it is for Esri Geodatabase (File Geodb) reader. For most other databases the FeatureReader WHERE applies to all feature types that are read (which isn't that useful).

The plan is to update the FeatureReader to support all the reader feature type parameters.

That worked! Thank you