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ASA Database Administration Guide
Database Options
Alphabetical list of options
Determines whether query processing is optimized towards returning the first row quickly, or minimizing the cost of returning the complete result set.
first-row, all-rows
all-rows
The OPTIMIZATION_GOAL option controls whether Adaptive Server Anywhere optimizes SQL data manipulation language (DML) statements for response time or total resource consumption.
If the option is set to all-rows (the default), then Adaptive Server Anywhere optimizes a query so as to choose an access plan with the minimal estimated total retrieval time. Setting OPTIMIZATION_GOAL to all-rows may be appropriate for applications that intend to process the entire result set, such as PowerBuilder DataWindow applications. A setting of all-rows is also appropriate for insensitive (ODBC static) cursors since the entire result is materialized when the cursor is opened. It may also be appropriate for scroll (ODBC keyset-driven) cursors, since the intent of such a cursor is to permit scrolling through the result set.
If the option is set to first-row, Adaptive Server Anywhere chooses an access plan that is intended to reduce the time to fetch the first row of the query's result, possibly at the expense of total retrieval time. In particular, the Adaptive Server Anywhere optimizer will typically avoid, if possible, access plans that require the materialization of results in order to reduce the time to return the first row. With this setting, the optimizer favors access plans that utilize an index to satisfy a query's ORDER BY clause, rather than plans that require an explicit sorting operation.
You can use the FASTFIRSTROW table hint in a query's FROM clause to set the optimization goal for a specific query to first-row, without having to change the OPTIMIZATION_GOAL setting.
For more information about using the FASTFIRSTROW table hint, see FROM clause.