Click here to view and discuss this page in DocCommentXchange. In the future, you will be sent there automatically.

SQL Anywhere 11.0.0 » UltraLite - Database Management and Reference » UltraLite SQL Reference » UltraLite SQL elements reference » Execution plans in UltraLite

 

Viewing an UltraLite execution plan

As a development aid, you can use Interactive SQL to display an UltraLite plan that summarizes how a prepared statement is to be executed. The text plan is displayed in the Interactive SQL Plan Viewer.

In UltraLite, an execution plan is strictly a short textual summary of the plan. No other plan types are supported. However, being a short plan, it allows you to compare plans quickly, because information is summarized on a single line.

To view an execution plan in the Plan Viewer

  1. From the Tools, choose Plan Viewer.

    The Plan Viewer appears in a separate window.

  2. Type a query in the SQL pane.

  3. Click Get Plan to generate a plan for the specified SQL statements.

    The plan appears in the lower pane of the Plan Viewer.

Example

Consider the following statement:

SELECT I.inv_no, I.name, T.quantity, T.prod_no
FROM Invoice I, Transactions T
WHERE I.inv_no = T.inv_no;

This statement might produce the following plan:

join[scan(Invoice,primary),index-scan(Transactions,secondary)]

The plan indicates that the join operation is accomplished by reading all rows from the Invoice table (following index named primary). It then uses the index named secondary from the Transactions table to read only the row whose inv_no column matches.

See also