pg_migrate(5)

NAME

PostgreSQL ORM migration

SYNOPSIS

    201305041232_migration_file.hs COMMAND [--with-db-commit]

DESCRIPTION

A Migrations is an executable Haskell source file (e.g. a Haskell source file with a "main :: IO ()" function, runnable by runghc). It must respond to the commands "up" and "down" by running a migration and rollback, respectively. Unless the "--with-db-commit" flag is set, the result of the migration or rollback should not be committed to the database.

While you can implement a migration however you like, the module Database.PostgreSQL.Migrations in the postgresql-orm package defines a function called defaultMain that implements most of the boiler plate functionality of a migration. You need only implement the actual migration and rollback code.

COMMANDS

  up

Upgrade the database by running the migration

  down

Downgrade the database by rolling back the migration

FLAGS

  --with-db-commit

MUST be included in order to actually commit the migration or rollback to the database. If this argument is not included, a test run is implied, and the migration should affect the database, probably by rolling back the transaction before exiting.

SEE ALSO

pg_migrate(1), runghc(1)