Safe Haskell	None
Language	Haskell2010

Database.PostgreSQL.PQTypes.Model.Migration

Description

Using migrations is fairly easy. After you've defined the lists of migrations and tables, just run migrateDatabase:

tables :: [Table]
tables = ...

migrations :: [Migration]
migrations = ...

migrateDatabase options extensions domains tables migrations

Migrations are run strictly in the order specified in the migrations list, starting with the first migration for which the corresponding table in the DB has the version number equal to the mgrFrom field of the migration.

Synopsis

data DropTableMode
- = DropTableCascade
- | DropTableRestrict
data MigrationAction m
- = StandardMigration (m ())
- | DropTableMigration DropTableMode
data Migration m = Migration {
- mgrTableName :: RawSQL ()
- mgrFrom :: Int32
- mgrAction :: MigrationAction m
}
isStandardMigration :: Migration m -> Bool
isDropTableMigration :: Migration m -> Bool

Documentation

data DropTableMode Source #

Whether to also drop objects that depend on the table.

Constructors

DropTableCascade	Automatically drop objects that depend on the table (such as views).
DropTableRestrict	Refuse to drop the table if any objects depend on it. This is the default.

data MigrationAction m Source #

Migration action to run, either an arbitrary MonadDB action, or something more fine-grained.

Constructors

StandardMigration (m ())	Standard migration, i.e. an arbitrary `MonadDB` action.
DropTableMigration DropTableMode	Drop table migration. Parameter is the drop table mode (`RESTRICT`/`CASCADE`). The `Migration` record holds the name of the table to drop.

data Migration m Source #

Migration object.

Constructors

Migration
Fields mgrTableName :: RawSQL () The name of the table you're migrating. mgrFrom :: Int32 The version you're migrating from (you don't specify what version you migrate TO, because version is always increased by 1, so if `mgrFrom` is 2, that means that after that migration is run, table version will equal 3 mgrAction :: MigrationAction m Migration action.

isStandardMigration :: Migration m -> Bool Source #

isDropTableMigration :: Migration m -> Bool Source #