Usage limits¶
The E-Maj extension usage has some limits:
- The minimum required PostgreSQL version is 9.5.
- All tables belonging to a “ROLLBACKABLE” tables group must have an explicit PRIMARY KEY.
- UNLOGGED and WITH OIDS tables can only be members of “audit_only” tables groups.
- TEMPORARY tables are not supported by E-Maj.
- Using a global sequence for a database leads to a limit in the number of updates that E-Maj can manage throughout its life. This limit equals 2^63, about 10^19 (but only 10^10 on oldest platforms), which still allow to record 10 million updates per second (100 times the best performance benchmarks results in 2012) during … 30,000 years (or at worst 100 updates per second during 5 years). Would it be necessary to reset the global sequence, the E-Maj extension would just have to be un-installed and re-installed.
- If a DDL operation is executed on an application table belonging to a tables group, E-Maj is not able to reset the table in its previous state. (more details here)