Firehose, Firehose block, and Fast Forward-Only Cursors

Firehose cursors deliver a streamlined, unmanaged, client-side cursor-processing mechanism for handling result sets from a DataServer query. When connection pooling is enabled, firehose cursors are the default mechanism for handling read-only results. If a firehose cursor is denied to an application, the DataServer first attempts to substitute a Fast Forward-Only (FFO) server-side cursor with Auto-Fetch and Auto-Close attributes in its place. If the query cannot be handled by a FFO cursor, the cursor is further downgraded.

A firehose block cursor is the default cursor processing mechanism to process the NO-LOCK queries for the DataServer for the MS SQL Server. It provides optimum performance for NO-LOCK queries and generally, surpass the performance benefits of the server-side block cursors because a firehose block cursor does bulk processing at the client-side.