ALTER OUTLINE

Purpose

This statement is supported only for outlines created by using the SQL_TEXT option. You can use this statement to add binding outlines and throttling rules.

Syntax

ALTER OUTLINE outline_name ADD stmt [ TO target_stmt ]

Parameters

Examples

• Add a throttling rule by using the ALTER OUTLINE statement.

  obclient> CREATE TABLE tbl1 (col1 NUMBER, col2 NUMBER);
  obclient> CREATE OUTLINE outline1 ON SELECT /*+max_concurrent(1)*/ * FROM tbl1 WHERE col1 =1 AND col2 = 1;
  obclient> ALTER OUTLINE outline1 ADD SELECT /*+max_concurrent(1)*/ * FROM tbl1 WHERE col1 =1 AND col2 = ?;
  obclient> ALTER OUTLINE outline1 ADD SELECT /*+max_concurrent(1)*/ * FROM tbl1 WHERE col1 =? AND col2 = 1;
  

• You can create multiple throttling statements for the same signature.

  obclient> CREATE TABLE tbl2 (col1 NUMBER, col2 NUMBER);
  obclient> CREATE OUTLINE olt_2 ON SELECT /*+max_concurrent(1)*/ c2,c1  FROM t1 WHERE c1 > 3 AND c2 = 1;
  obclient> ALTER OUTLINE olt_2 ADD SELECT /*+max_concurrent(2)*/ c2,c1  FROM t1 WHERE c1 > ? AND c2 = 1;
  obclient> ALTER OUTLINE olt_2 ADD SELECT /*+max_concurrent(2)*/ c2,c1  FROM t1 WHERE c1 > ? AND c2 = 2;
  obclient> ALTER OUTLINE olt_2 ADD SELECT /*+max_concurrent(0)*/ c2,c1  FROM t1 WHERE c1 > ? AND c2 = 3;
  

Considerations

• Only one execution plan can be specified for the same outline_name. If an execution plan is specified by using the CREATE OUTLINE statement, you cannot add another execution plan by using the ALTER OUTLINE statement.

• Like the CREATE OUTLINE statement, the ALTER OUTLINE statement cannot specify both a throttling rule and an execution plan.

• When you execute the ALTER OUTLINE statement, the outline_name and signature must match.