One question that comes up very often is which version of Pgpool II is supported with which database server? I would like to address this question in this post. For a bit of background, Pgpool II is a middleware product that sits between the client and the database server in both PostgreSQL and EDB Postgres Advanced Server architectures and provides functionality like connection pooling, load balancing, high availability, etc. While Pgpool II is a community product, EnterpriseDB (EDB) ships its own version of Pgpool II because of the proprietary enhancements added to the community Pgpool. The changes are done to support the EDB protocol extensions like stored procedure support, redwood style sequences, etc.
The table below shows the version of the EDB Pgpool II along with the corresponding EDB Postgres Advanced Server (EPAS) version it is shipped with. This means that the EPAS server and Pgpool II is supported and tested in the variation given below. The latest version of community pgpool II is 3.7, EDB pgpool II 3.7 is not released yet.
| EPAS Version | Pgpool II Version |
| 10 | 3.6.9 |
| 9.6 | 3.5.13 , 3.6.19 |
| 9.5 | 3.4.16 |
| 9.4 | 3.3.20 , 3.4.16 |
| 9.3 |
3.3.20 |
In addition to pgpool II main application, EDB also provides the installation for pgpool II extensions. The pgpool II extensions are installed as part of the database server.
The table below provides the version of pgpool II extensions and the EPAS version it supports. Please note that the pgpool II extension versions below are same in terms of functionality.
| EPAS Version | Pgpool II extension version |
| 10 | 3.6.9 |
| 9.6 | 3.5.13 |
| 9.5 | 3.4.16 |
| 9.4 | 3.3.20, 3.4.16 |
Please note that minor version will get changed after a minor version update is applied..