SQL/MX 3.2 Installation and Upgrade Guide (H06.25+, J06.14+)

Table Of Contents

Consider the following scenarios for system fallback:

• Executing the DOWNGRADE command is not necessary in the following scenarios:

The fallback version is SQL/MX Release 3.1 and the database contains v3100, v3000

and v1200 schemas only.

◦

◦ The fallback version is SQL/MX Release 3.0 and the database contains v3000 and

v1200 schemas only.

◦ The fallback version is SQL/MX Release 2.3.x and the database contains v1200 schemas

only.

• If you are using new database features for some objects in v3200 metadata, you must perform

the following steps:

◦ Use the FEATURE_VERSION_INFO function to obtain the name and object type of database

objects that use new features. Such objects prevent a downgrade operation. For more

information, see SQL/MX Functions and Expressions in the SQL/MX Reference Manual.

◦ Convert each database object that uses new features to a corresponding copy object

without new features. For copy objects, you create a copy of the original object without

the new features, so as to retain the data. For example, a table with an IDENTITY column

(a v3100 feature) prevents a metadata downgrade to v3000 or v1200. However, the

table may contain important data and cannot just be dropped. In this scenario, you can

create a copy of that table with an ordinary column instead of the identity column.

◦ Drop the old unsupported objects before executing the DOWNGRADE command.

◦ Downgrade to the required version. For more information on how to use the downgrade

utility, see SQL/MX Utilities in the SQL/MX Release 3.2 Reference Manual.

Stopping TMF

Before a system fallback, stop TMF twice with no database activity between the two stops:

TMF 1> STOP TMF

TMF 2> START TMF

TMF 3> STOP TMF

These steps are necessary to avoid volume recovery when TMF is started after the system fallback.

TMF recovery of SQL/MX database objects will access the RCBs of the affected objects. You must

shut down TMF because the RCBs of the affected objects are not immediately compatible after a

change from SQL/MX Release 3.2 to an earlier release.

NOTE: Do not fall back from SQL/MX Release 3.2 immediately after a system crash. In case of

a system crash, you must restart the system with the version that was running at the time of the

crash, start TMF, and then shut down TMF twice before falling back.

Installing SQL/MX Release 3.0 or Release 3.1

To fall back to SQL/MX Release 3.0 or Release 3.1, complete the following steps:

1. Install SQL/MX Release 3.0 or Release 3.1. For more information on installing SQL/MX

Release 3.0 or Release 3.1, see “Installing SQL/MX” (page 14) .

2. Install the fallback SPRs referred to in the SQL/MX Release 3.2 softdoc, if any.

3. Perform the required changes to your system after falling back. See “Changes required after

falling back” (page 54).

52 Falling back from SQL/MX Release 3.2