SQL Optimizer for SAP ASE 3.8 - Installation Guide

Forces (Pre-ASE 15)

The Forces page on the Optimization for Pre-ASE 15 tab of the Preferences window allows you to decide if you would like to have the Adaptive Server forces applied to alternative SQL statements. By adding an Adaptive Server force, you can force the Adaptive Server’s internal optimizer to choose a particular query plan.

Set

Set Forceplan On

Specify whether to enforce the tables to be joined in the order specified in the FROM clause.

Set Sort_Merge On/Off

{Adaptive Server 15 or later}

Specify whether to consider using merge joins. If selected, the parameter will toggle against the server sort_merge setting.

Set JTC On/Off

{Adaptive Server 15 or later}

Specify whether to use join transitive closure. If selected, the parameter will toggle against the server JTC setting.

Set Table Count

{Adaptive Server 15 or later}

Specify the number of tables that the optimizer considers at one time while determining table join order.

Parallel force

PARALLEL

Specify whether to enforce the use of a particular parallelism degree to access the table if parallel query is enabled in the database server.

Index force

INDEX

Specify whether to enforce the use of a particular index to access the table.

Note: The forces that are marked with an asterisk are counted in the Number of forces selected on the Quota Preferences page.

Related Topics

SQL Optimizer Overview

Intelligence Level

Optimization Preferences

Quotas

Abstract Plan Preferences