Getting Startedwith pureQuery
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<strong>Getting</strong> Started with <strong>pureQuery</strong><br />
6.6.2.2 Changes to statement sets<br />
When you configure a <strong>pureQuery</strong>Xml file that has previously been configured, the default<br />
behavior of the Configure utility is to attempt to preserve how statements are grouped into<br />
statement sets by processing only the statement sets that need to be processed. You can<br />
specify the option -cleanConfigure with the value TRUE to direct <strong>pureQuery</strong> to process<br />
all of the statements without attempting to preserve their groupings.<br />
In a <strong>pureQuery</strong>Xml file, each statementSet element has a configureStatus attribute<br />
that is set to REQUIRED, AUTO, or FINAL. These values dictate how the Configure utility<br />
treats the statement sets. The utility does not configure a statement set for which the<br />
configure status is FINAL, if the statement set has a base package name. The utility only<br />
configures AUTO packages when necessary, and it always configures REQUIRED<br />
packages. When you specify the option -cleanConfigure with the value TRUE to the<br />
Configure utility, the utility makes no attempt to preserve the groupings of the statements in<br />
the file. It configures all of the SQL statements and creates new statement sets to contain<br />
them.<br />
If you manually edit a statement set, you must change the configureStatus to<br />
REQUIRED. Otherwise, the Configure utility might not configure the statement set, and its<br />
resulting contents could be invalid. When the Configure utility configures a statement set, it<br />
performs some checks on the contents of the statement set, and it stores information in the<br />
statement set that the StaticBinder utility needs to bind the packages. Changes to the<br />
contents of a statement set can result in changes to the information necessary to bind the<br />
package correctly. IBM recommends that you only modify <strong>pureQuery</strong>Xml files by<br />
capturing, by configuring, and by using the IBM Optim Development Studio <strong>pureQuery</strong>XML<br />
editor. Doing so causes the configureStatus attribute to be managed appropriately,<br />
and it otherwise helps to keep the contents of the file in a legal state.<br />
6.6.3 DDL statements<br />
DDL statements can cause problems in applications that execute SQL statically. When an<br />
application runs DDL statements that modify tables or other database objects, the IBM ®<br />
DB2 Database automatically invalidates any packages that reference those database<br />
objects. If the application then attempts to execute an SQL statement in an invalidated<br />
package, the database automatically tries to re-bind the package. The access plans that<br />
the re-bind uses can be different from those of the original package, and they might be less<br />
optimal than the original plans. Consequently, if your application runs DDL statements,<br />
you should review the SQL statements to determine if they will cause problems for the<br />
database packages that your application will use.<br />
The Configure utility puts DDL statements and non-DDL statements into separate<br />
statement sets. It also generates a separate file with the extension .ddl that contains the<br />
DDL statements that are in the file. This file can help you to determine which DDL<br />
statements your application executes, and you can use it to know the SQL statements that
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