E-Maj: logs and rollbacks table updates
This software is distributed under the GNU General Public License.
The main goals of E-Maj are:
- log updates performed on one or several sets of tables.
- cancel these updates if needed, and reset a tables set to a predefined stable state.
In development environments, it brings a good help in testing application, providing an easy way to rollback all updates generated by programs execution, and replay these processings as many times as needed.
In production environments, it brings a good solution to:
- keep an history of updates performed on tables to examine them in case of problem
- set inter-batch savepoints on group of tables,
- easily "restore" this group of tables at a stable state, without being obliged to stop the cluster,
- handle several savepoints during batch windows, each of them been usable at any time as "restore point".
It brings a good alternative to the management of several disk images.
In both environments, being able to examine the history of updates performed on tables can be very helpful in debugging work or for any other purpose.
3- Supplied files
- README this readme file
- CHANGES release notes
- LICENSE license information
- AUTHORS who is behind E-Maj
- META.json meta file for PGXN
- sql/emaj.sql psql installation script
- sql/check-0.10.1-to-0.11.0-conditions.sql psql script to check that all conditions allowing a
direct migration from 0.10.1 to 0.11.0 are met
- sql/emaj-0.10.0-to-0.10.1.sql psql migration script from 0.10.0 to 0.10.1
- sql/emaj-0.10.1-to-0.11.0.sql psql migration script from 0.10.1 to 0.11.0
- sql/emaj-0.11.0-to-0.11.1.sql psql migration script from 0.11.0 to 0.11.1
- sql/emaj--0.10.0--unpackaged.sql script used to unregister a 0.10.0 E-Maj extension
- sql/emaj--0.10.1--unpackaged.sql script used to unregister a 0.10.1 E-Maj extension
- sql/uninstall.sql uninstallation script
- sql/demo.sql demonstration psql script
- sql/prep-pr.sql psql script to prepare parallel rollback demonstration
- doc/emaj.0.11.1_doc_en.pdf E-Maj user's guide in English
- doc/emaj.0.11.1_doc_fr.pdf E-Maj user's guide in French
- doc/emaj.0.11.1_pres_en.pdf E-Maj presentation in English
- doc/emaj.0.11.1_pres_fr.pdf E-Maj presentation in French
- php/emajParallelRollback.php external client for parallel rollback
4- How to install and use E-Maj
All the information details needed to install and use E-Maj are provided in the user's guide that is included in the supplied .tar file.
To reach this user's guide, just untar the supplied file by :
tar -xvzf emaj-<version>.tar.gz
Unfortunately, due to current limitations in EXTENSION management by PostgreSQL, it is not possible to install E-Maj as a standart EXTENSION.
Remark: The user's guide also presents an emaj plugin for phpPgAdmin. In its current implementation, this plugin is very invasive inside phpPgAdmin code. For this reason, this plugin is currently not yet available on pgfoundry. But if you wish to get a copy, simply ask me.
For additional support or bug report, please contact Philippe BEAUDOIN (phb <dot> emaj <at> free <dot> fr).
Any feedback is welcome, even to just notice you use E-Maj.