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SQL Optimizer for Oracle 9.3.3 - User Guide

Welcome to SQL Optimizer
About SQL Optimizer SQL Optimization Workflow New in This Release Additional Resources Database Privileges Database Privileges Script Connect to the Database Windows Layout Customize Toolbars Keyboard Shortcuts Support Bundle Register SQL Optimizer Check for Updates SQL Operations
ALL PARTITION ALTER INDEX AND EQUAL ANTI JOIN BITMAP AND BITMAP COMPACTION BITMAP CONSTRUCTION BITMAP CONVERSION BITMAP INDEX BITMAP JOIN INDEX UPDATE BITMAP JOIN INDEX UPDATE STATEMENT BITMAP KEY ITERATION BITMAP MERGE BITMAP MINUS BITMAP OR BUFFER SORT CARTESIAN JOIN COLLECTION ITERATOR CONCATENATION CONNECT BY CONNECT BY PUMP COUNT COUNT STOPKEY CREATE AS SELECT CUBE SCAN DDL STATEMENT DELETE DOMAIN INDEX FAST FULL INDEX SCAN FILTER FIRST ROWS FIXED INDEX FIXED TABLE FOR UPDATE FULL INDEX SCAN FULL INDEX SCAN DESCENDING FULL INDEX SCAN (MIN/MAX) HASH GROUP BY HASH GROUP BY PIVOT HASH JOIN HASH JOIN BUFFERED HASH PARTITION HASH UNIQUE INDEX INDEX BUILD NON UNIQUE INDEX RANGE SCAN INDEX RANGE SCAN DESCENDING INDEX RANGE SCAN (MIN/MAX) INDEX SAMPLE FAST FULL SCAN INDEX SKIP SCAN INDEX SKIP SCAN DESCENDING INDEX UNIQUE SCAN INLIST ITERATOR INLIST PARTITION INSERT INTERSECTION INTO INVALID PARTITION ITERATOR PARTITION LOAD AS SELECT MAT_VIEW ACCESS MAT_VIEW REWRITE ACCESS MERGE JOIN MINUS MULTI-TABLE INSERT NESTED LOOPS OUTER JOIN PARTITION PARTITION HASH EMPTY PARTITION LIST PARTITION RANGE PROJECTION PX BLOCK ITERATOR PX COORDINATOR PX ITERATOR PX PARTITION PX PARTITION HASH ALL PX PARTITION LIST ALL PX PARTITION RANGE ALL PX RECEIVE PX SEND RANGE PARTITION RECURSIVE EXECUTION RECURSIVE WITH PUMP REFERENCE MODEL REMOTE SELECT SEMI JOIN SEQUENCE SINGLE PARTITION SINGLE RANGE PARTITION SORT SORT AGGREGATE SORT GROUP BY SORT GROUP BY CUBE SORT GROUP BY NOSORT SORT GROUP BY ROLLUP SORT JOIN SORT ORDER BY SORT UNIQUE SQL MODEL TABLE ACCESS TABLE ACCESS BY GLOBAL INDEX ROWID TABLE ACCESS BY INDEX ROWID TABLE ACCESS BY LOCAL INDEX ROWID TABLE ACCESS BY ROWID TABLE ACCESS BY USER ROWID TABLE ACCESS CLUSTER TABLE ACCESS FULL TABLE ACCESS HASH TABLE ACCESS SAMPLE TABLE QUEUE TEMP TABLE GENERATION TEMP TABLE TRANSFORMATION UNION UNION ALL UNION ALL (RECURSIVE WITH) UNPIVOT UPDATE VIEW VIEW PUSHED PREDICATE WINDOW
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View SQL Information (Scan SQL)

To view SQL information

  1. Select the Scan SQL tab in the main window.
  2. Click beside the Group list and select a group.

  3. Select a job in the Job List pane.

  4. Select a SQL statement in the SQL List pane.

  5. Select the SQL Information tab.

  6. Click the following to view the information that displays for each pane.

    ClosedClassification
    ClosedConversion

  

Related Topics

About Scanning SQL

Scan SQL

 

Filter Columns

This topic focuses on information that may be unfamiliar to you. It does not include all step and field descriptions.

To filter a column

» Click to the right of the column header and select a filtering option.

Note: When filtering is applied to columns, displays to the right of the column header. A Filter panel also displays at the bottom of the grid that describes applied filters as illustrated in the following:

Tips:

  • Click in the Filter panel to clear a filter or right-click a filtered column and select Clear Filter.

  • Click in the Filter panel to enable or disable a filter.

  • Click in the Filter panel to select a previously defined filter.

 

Use Execution Plans

About Execution Plans

The execution plan displays the steps a database takes to execute a SQL statement. You can use the execution plan to determine if a statement is efficient.

In the step formats (like Tree Plan) each step indicates how SQL Optimizer retrieves rows of data. The steps are numbered in the order of execution to make the plan easier to read.

Oracle executes each child operation before the parent operation. For some SQL statements, Oracle executes the parent operation once it retrieves a single row from the child operation. Other SQL statements require that Oracle retrieve all rows from the child operation before it executes the parent operation.

Reviewing Execution Plans

Use the Execution Plan window to review the execution plan for the original SQL statement or selected alternative. Several display options and configurations are available.

You can select an execution plan format, configure plan content, and customize plan text.

To select a plan format

  1. Right-click the execution plan and select View Plan | option.
  2. Select one of the following formats:
    • Tree Plan—Displays plan as tree view with numbered steps.
    • DBMS_XPlan (Formatted)—Displays plan using the DBMS_XPLAN output with added formatting.
    • DBMS_XPlan (Plain Text)—Displays plan using the DBMS_XPlan output as plain text. This is the format returned by Oracle.
    • Graphic Plan—Displays a graphic view of the plan. Includes numbered steps.
    • MS Graphic Plan—Displays a graphic type view. Includes numbered steps.
    • Plain Language Plan—Lists steps using descriptions in plain language.
  3. Go to Review Execution Plans to learn more about the different plan formats and how to customize them.

Execution Plan Window - Optimize SQL

The Execution Plan window displays the available execution plans. Each tab contains a different type of execution plan.

  • Default Plan—The Default Plan tab displays the execution plan chosen by Oracle and is retrieved using the EXPLAIN PLAN statement. Click to retrieve the default plan after entering/importing the original SQL.

  • Actual Plan—The Actual Plan is retrieved from the plan cache after execution and is the actual execution plan performed by the database to execute the statement.

  • Virtual Plan—The Virtual Plan tab is displayed for indexes when you generate index alternatives in an Optimize SQL, SQL Rewrite session. See Fill Missing Execution Plans for more information about retrieving other execution plans for index alternatives.

Execution Plan Actions

Right-click in the Execution Plan window to select from the following actions:

Action

Description

Copy

Copies the execution plan to the clipboard.

Save

Saves the execution plan as a .jpg file. The DBMS_XPlan formats can be saved as a .txt file also.

Print

Opens the print window so you can print the execution plan.

View Plan

Allows you to change how the execution plan is displayed.

Step Description Select this option to display a description of the selected step in the Execution Plan pane footer.
Plan Information

If you select this option, SQL Optimizer identifies whether an execution plan uses any of the following: cardinality feedback, dynamic sampling, SQL plan directives, or adaptive plan. If applicable, the information displays in the Execution Plan pane directly above the Execution Plan tab.

Animate Plan Steps

Highlights, one-by-one, the execution plan steps.

Plan Options

Opens the Execution Plan Options window so you can select which information is displayed in the execution plan and whether to display specific items as a column.

Help on plan step

Displays the help text for the currently selected step in the execution plan.

Help on Execution Plan

Opens online help for the Execution Plan window.

 

Related Topics

Retrieve Execution Plans

Review Execution Plans

Fill Missing Execution Plans

Copy Execution Plans

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