[LUCENE-762] [PATCH] Efficiently retrieve sizes of field values

• Type: New Feature
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 2.1
• Component/s: core/store
• Assignee: Grant Ingersoll
• Reporter: Chuck Williams
• Created: 28/Dec/06 10:52
• Updated: 28/Aug/22 11:33
• Resolved: 09/Feb/07 03:19

Description

Sometimes an application would like to know how large a document is before retrieving it. This can be important for memory management or choosing between algorithms, especially in cases where documents might be very large.

This patch extends the existing FieldSelector mechanism with two new FieldSelectorResults: SIZE and SIZE_AND_BREAK. SIZE creates fields on the retrieved document that store field sizes instead of actual values. SIZE_AND_BREAK is especially efficient if one field comprises the bulk of the document size (e.g., the body field) and can thus be used as a reasonable size approximation.