MX Database and Application Migration Guide

Version Management and Interoperability

HP NonStop SQL/MP to NonStop SQL/MX Database and Application Migration Guide—666211-001

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SQL/MX Query Plan and Module Versions

Displaying the OFV

This example displays the OFV of a specified database object, where the table name,

tlarge is a value that you specify:

>>get version of table tlarge;

OBJECT SCHEMA VERSION: 3000

OBJECT FEATURE VERSION: 3000

--- SQL operation complete.

The following is an example of feature_version_info function:

>>select object_name, feature_version

from table (feature_version_info ('CATALOG', 'CATX', 1200));

OBJECT_NAME FEATURE_VERSION

CATX."schema x"."table with large key" 3000

CATX.SCHEMAY."table with bignum column" 3000

FEATURE_VERSION_INFO is a built-in table-valued function that returns feature

version information for all user objects with an OFV higher than a given value, in a

specified set of catalogs. For more information, see the

SQL/MX Reference Manual.

The MXCI SHOWLABEL command also displays OSV and OFV information.

SQL/MX Query Plan and Module Versions

Query plan versioning is a set of mechanisms that allow SQL/MX software to assign a

version to query execution plans and user modules and to determine if the version of a

query execution plan or module is compatible with the MXV. Query plan versions

include the plan version and module version.

Plan Versions

The query execution plan of a SQL statement is assigned a plan version depending on

the SQL/MX release that is installed on the node where the plan is compiled.

NonStop SQL/MX successfully compiles and executes a query execution plan if the

following conditions are met:



the plan version is higher than or equal to the earliest supported plan version.



the plan version is lower than or equal to the current plan version of the node

where the plan is being executed.

Otherwise, NonStop SQL/MX returns a versioning error.