Work with a database

Three databases run the same way the frameworks do, as an environment rather than a run: PostgreSQL, MySQL and MongoDB.

You get a database terminal: a prompt that speaks the query language rather than the shell, so writing a query is the same thing it is anywhere else.

What it is good for

• Trying a query

  Write it, run it, see what comes back, without connecting to anything real.

  Good for working out the query before you point it at data that matters.

• Teaching or being taught

  Everybody gets the same database in the same state, with nothing to install first.

  Good for a class, a workshop, or a shared example.

What persists

The database is part of the environment, so what you create stays there between visits until you reset it. You can build up a schema over several sittings.

What next

Once something works, sharing it is a separate question, and who you can share with depends on whether you are on a team.