Database dependency not included by default

[SAB13711]

I get the below error:

error:psycopg2 is required for PostgreSQL connections. Install: pip install psycopg2-binary

It seems that psycopg2-binary is required, but not included in the framework by default.

[SAB13711]

This is by design it seems. Just need it documented.

[MichaelC8E]

Confirmed on tina4-python 3.13.5

psycopg2 is required for PostgreSQL — the adapter lazy-imports it at postgres.py:54-58 and raises if missing. METADATA declares it only under Requires-Dist: psycopg2-binary>=2.9; extra == 'postgres', so pip install tina4-python resolves with zero deps as intended. Same pattern for the other five drivers (mysql.py:31, mssql.py:31, firebird.py:118, mongodb.py:350, odbc.py:33).

The extras already exist — METADATA lines 145-155 list tina4-python[postgres], [mysql], [mssql], [firebird], [mongo], [odbc], [all-db]. PyPI and the repo README both render that block.

The gap is on the book side: https://tina4.com/python/01-getting-started.html never mentions a driver requirement, and https://tina4.com/python/05-database.html flags the requirement but recommends uv add psycopg2-binary (bare driver) rather than the extras form. A one-line prerequisites callout in Getting Started, and switching the install block in Chapter 5 to uv add 'tina4-python[postgres]', would close it.

Alternatives, if a UX change is on the table

• Bundle into base deps. Move psycopg2-binary (or all six drivers) out of extras and into unconditional Requires-Dist. Simplest install path, but breaks the "zero-dependency" framing in Ch1 / PyPI / repo README and forces the driver on every user — including SQLite-only and non-DB projects. Prebuilt wheels cover most platforms but not all (some Alpine/ARM/musl combos fall back to source build needing libpq-dev).
• Baseline subset. Ship tina4-python with a small default like [postgres,mysql] pre-included. Caps bloat versus full bundle but still drops the strict zero-dep claim and still forces drivers on users who don't need them.
• Scaffolder flag. tina4 init python --db=postgres writes tina4-python[postgres] into the generated pyproject.toml directly. Keeps the base zero-dep, makes the right install happen at project creation, no runtime ImportError.

[andrevanzuydam]

Fixed in v3.13.6 — just published to PyPI.

The ImportError you saw is now multi-line and suggests both uv and pip. Same treatment applied to MySQL, MSSQL, Firebird, ODBC, and MongoDB drivers, plus the MongoDB queue backend:

psycopg2 is required for PostgreSQL connections. Install one of:
    uv add tina4-python[postgres]   # extra for projects using uv
    pip install psycopg2-binary    # bare driver
    uv add tina4-python[all-db]    # all five database drivers

Cross-framework parity (per the v3 maintenance discipline): same change shipped to Ruby (bundle add + gem install) and Node (npm + yarn + pnpm + bun). PHP's apt-get / brew hints were already in place.

Release notes: https://github.com/tina4stack/tina4-book/blob/main/book-1-python/chapters/36-releases.md

Closing left to you — let me know if the hint isn't clear enough or if anything looks off after upgrading.