REVERT: Revert Database to Lower Version

The REVERT function starts from the Adabas version of the last nucleus session.

graphics/util_adacnv_revert.png

This document covers the following topics:


Essential Parameter and Subparameter

TOVERS: Target Version

The version of Adabas database (version and revision level) to achieve at the end of the ADACNV run. The TOVERS parameter value must be a version lower than the source version.

The version format is vr indicating the version and release level; for example, 84 or 85.

Optional Parameter

IGNPPT: Ignore Parallel Participant Table PLOG Entries

When reverting from a version of Adabas that uses the parallel participant table (PPT) structure to a lower version of Adabas, an error is printed and conversion fails if the system detects one or more protection logs (PLOGs) from the current version that have not been copied/merged.

If IGNPPT is specified, the utility will continue processing in spite of the uncopied/unmerged PLOGs.

NOUSERABEND: Termination without Abend

When a parameter error or a functional error occurs while this utility function is running, the utility ordinarily prints an error message and terminates with user abend 34 (with a dump) or user abend 35 (without a dump). If NOUSERABEND is specified, the utility will not abend after printing the error message. Instead, the message "utility TERMINATED DUE TO ERROR CONDITION" is displayed and the utility terminates with condition code 20.

Note:
When NOUSERABEND is specified, we recommend that it be specified as the first parameter of the utility function (before all other parameters). This is necessary to ensure that its parameter error processing occurs properly.

PLOGDEV: Multiple PLOG Device Type

PLOGDEV specifies the physical device type on which the multiple protection log data sets to be reverted is contained. If PLOGDEV is not specified, the device type specified by the ADARUN DEVICE parameter is used.

RESTART: Rerun after Point of No Return

If ADACNV terminates abnormally after the point-of-no-return, that is, after all changed blocks have been written to DD/FILEA, the RESTART parameter instructs ADACNV to begin its run by reading the contents of DD/FILEA and continue by writing them to the database.

TEST: Test Conversion

The TEST parameter tests the feasibility of the reversion operation without actually writing any changes to the database.

Reversion Considerations

The following is a list of special reversion considerations for ADACNV.

For information about reverting back to versions prior to Adabas 8.2, refer to the Adabas 8.2 Release Notes. To access a copy of these, read Documentation and Other Online Information.

All Versions
  • Reversion is not possible if any Adabas feature is used in the current version that is not supported in the target version. This statement applies to all Adabas features that affect the structure of the database.

From Version 8.4 to a version prior to 8.3.2

ADACNV will not allow you to REVERT the database to a version prior to Adabas 8.3 if the nucleus has been run with INDEXUPDATE=ADVANCED, and files have actually been updated according to the advanced index structure rules.

If an Adabas nucleus has been run with INDEXUPDATE=ADVANCED, once files have actually been updated according to the advanced index structure rules, Adabas can no longer be directly downgraded to an earlier version. Prior to a downgrade, the indexes of those files must be rebuilt using the ADALOD or ADAORD utilities.

If the database is to be converted back to a version below 8.3, the ADACNV utility checks for files whose indexes have been updated according to the advanced index structure rules. If there is any such file, ADACNV declines to convert the database and terminates with ERROR-147:

File (fnr) has the advanced index structure.

The ADAREP utility can be used to list all files that have the advanced index structure. In the detail section of the file report, ADAREP prints a line saying

‘Index structure ... Advanced’

if the file has been updated according to the advanced index structure rules. Otherwise, the line says

‘Index structure ... Original.’

Utilities always build the index structure according to the original rules. The ADALOD and ADAORD utilities can be used to change indexes with the advanced structure back to the original structure. Any of the following functions can be used:

  • ADAULD UNLOAD followed by ADALOD LOAD

  • ADAORD REORASSO

  • ADAORD REORDB

  • ADAORD REORFASSO

  • ADAORD REORFILE

  • ADAORD RESTRUCTUREDB (REDB) followed by ADAORD STORE

  • ADAORD RESTRUCTUREF (REF) followed by ADAORD STORE

Caution:
Once the nucleus is run with INDEXUPDATE=ADVANCED, do not downgrade Adabas to version 8.3 SP1 if there are files in the database that have the advanced index structure. The Adabas 8.3 SP1 nucleus and utilities would recognize such indexes as inconsistent. Rather, before going back to Adabas 8.3 SP1, rebuild the indexes of those files using ADALOD or ADAORD, as described above.

From Version 8.3 to 8.2

ADACNV will not allow you to REVERT the database to Adabas 8.2 if any of the following apply:

  • The database contains a Security file in which a password is or was defined that applies to more than 191 files or relates to more security-by-value criteria than fit into a single data storage record. (This condition persists even if that password is deleted.)

  • The database contains a file in which a system field of type SECUID is defined.

Example

The following example indicates that the database should be converted back (reverted) to a version 8.4 Adabas database.

ADACNV REVERT TOVERS=84