Document Transformers are field-mapping functions that are part of the Indexing Pipeline, along with Geotagging and Metadata Extraction. Document Transformers allow you to manage and configure metadata during the indexing process. You can create, modify or duplicate fields as well as set field values using transformation functions.
IMPORTANT
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Document Transformers are case-sensitive. When you are configuring a Transformer, the field names must match the case and text of the existing fields EXACTLY. Mismatched cases can lead to duplicate field names as well as other serious errors in subsequent queries. These errors may be extremely difficult to diagnose and track down after the fact, and may ultimately require re-indexing your data after the issue has been resolved, so it is critical that you verify the field name and case before proceeding with any queries.
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Configuring Document Transformers
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You can also combine one or more of these in profiles that can be applied globally or to a specific location(s). See Document Transformer Profiles for more information.