Row Block Data Exchange

A row block is the data transfer area between the producer and the consumer.

A table UDF can only produce rows. It can use an existing row block, or it can build its own row block.

A TPF can both produce and consume rows. A TPF produces rows in the same way a table UDF produces rows and can use an existing row block or build its own row block. A TPF can consume rows from an input table and can provide the producer with a row block, or request the producer to create its own row block.

• Fetch Methods for Row Blocks
  The fetch methods for row blocks are _fetch_into_extfn and _fetch_block_extfn. These methods are part of the a_v4_extfn_table_func structure.
• Using a Row Block to Produce Data
  A table UDF or TPF can use row block structures to produce data.