Currently digiKam only supports MySQL/MariaDB as an external SQL server; adding PostgreSQL support would provide stability, flexibility, and wider adoption in professional environments.


SUMMARY
Add support for PostgreSQL as a database backend in digiKam (currently only MySQL/MariaDB supported).

STEPS TO REPRODUCE

Open digiKam.

Go to Setup → Database.

Only SQLite or MySQL/MariaDB are available as external SQL server options.

OBSERVED RESULT
Users can only host digiKam’s database on MySQL/MariaDB when an external SQL server is needed. PostgreSQL is not supported.

EXPECTED RESULT
digiKam should support PostgreSQL in addition to MySQL/MariaDB as an external database backend. This would give users more flexibility in choosing their preferred database system and allow integration with existing PostgreSQL infrastructures.

SOFTWARE/OS VERSIONS
Windows: Any supported
macOS: Any supported
Linux/KDE Plasma: Any supported
KDE Plasma Version: n/a
KDE Frameworks Version: n/a
Qt Version: n/a

ADDITIONAL INFORMATION
Reasons for PostgreSQL support:

Stability & Performance: PostgreSQL is known for robustness and high concurrency handling, which benefits large photo libraries.

Advanced Features: PostgreSQL offers advanced indexing, full-text search, JSON support, and extensions that could improve digiKam performance and search features.

Compatibility: Many enterprise and academic environments standardize on PostgreSQL. Supporting it lowers the barrier for adoption of digiKam in professional workflows.

Open Source Alignment: PostgreSQL’s strong open-source ecosystem aligns well with KDE’s philosophy.

Similar KDE applications (e.g., Akonadi, Kexi) already support PostgreSQL, making this a logical enhancement for digiKam’s database module.