Revert Elements

Database Management Reference Manual

Comparisons Across Sessions and Stamps : Revert Elements

Revert allows you to directly Revert an element or hierarchy of elements to a previous state.

>- REVert -+- ELEment ---.
           |             |
           `- HIERarchy -+- <selele> -+- AT -----.
                                      |          |
                                      `- BEFore -+- <comparison> ->

Where the <comparison> syntax is similar to that following the SINCE keyword in both of the existing DIFFERENCE and OUTPUT CHANGES commands.

-->-+- <date/time> -+-----------------------.
    |               |                       |
    |- LATEST ------|                       |
    |               |                       |
    |---------------+- EXTRACT -+-----------|
    |                           |           |
    |                           |- extno ---+
    |                           |           |
    |                           '- extname -+
    |                                       |
     `- STAMP - <name> ---------------------+->

If the BEFORE clause is used the elements will be reverted to the state they had before the session that is selected by the historical specification.

Examples of the Revert Command:

REVERT HIER /EQUIP AT LATEST

Reverts the element hierarchy rooted at /EQUIP to latest saved session.

REVERT HIER /EQUIP BEFORE LATEST

Reverts the hierarchy rooted at /EQUIP to the state it had before the latest saved session.

REVERT ELE /E1301 AT 20:16 26 / 3 / 2010

Reverts the single element /E1301 to the state it had on the given time and date.

REVERT HIER /PIPES AT STAMP /StampMilestone7

Reverts the hierarchy rooted at /PIPES to the state it had at the named stamp.

REVERT HIER CE AT EXTRACT

Reverts the hierarchy rooted at the current element to its state in the parent extract.

The revert command makes sure that every element creation, include, reorder and deletion, and every attribute change is allowed before proceeding. If any of these tests fail, for example due to legality checks, read-only databases or DACs, then the entire revert operation is cancelled and the following error is generated.

(43,615) Cannot Revert elements. No changes have been made.

In this case a series of warning messages is written to the console indicating the causes of the error, for example:

DAC prevents deletion of element /DELETE_UDET_B

DAC prevents creation of element =15752/1363

DAC prevents modification of attribute Built on element /MODIFY_B_VESS1

Element locks do not prevent a revert operation if those elements were unlocked in the previous state.

Note:

this command is not directly related to the REVERT <database name> command available in the Admin module. This command allows an entire database to be reverted to the state it had at a previous session.