Safe Haskell	None
Language	Haskell98

Database.Persist.Postgresql

Description

A postgresql backend for persistent.

Synopsis

Documentation

withPostgresqlPool Source #

Arguments

:: (MonadBaseControl IO m, MonadLogger m, MonadIO m, IsSqlBackend backend)
=> ConnectionString	Connection string to the database.
-> Int	Number of connections to be kept open in the pool.
-> (Pool backend -> m a)	Action to be executed that uses the connection pool.
-> m a

Create a PostgreSQL connection pool and run the given action. The pool is properly released after the action finishes using it. Note that you should not use the given ConnectionPool outside the action since it may be already been released.

withPostgresqlConn :: (MonadIO m, MonadBaseControl IO m, MonadLogger m, IsSqlBackend backend) => ConnectionString -> (backend -> m a) -> m a Source #

Same as withPostgresqlPool, but instead of opening a pool of connections, only one connection is opened.

createPostgresqlPool Source #

Arguments

:: (MonadIO m, MonadBaseControl IO m, MonadLogger m, IsSqlBackend backend)
=> ConnectionString	Connection string to the database.
-> Int	Number of connections to be kept open in the pool.
-> m (Pool backend)

Create a PostgreSQL connection pool. Note that it's your responsibility to properly close the connection pool when unneeded. Use withPostgresqlPool for an automatic resource control.

createPostgresqlPoolModified Source #

Arguments

:: (MonadIO m, MonadBaseControl IO m, MonadLogger m, IsSqlBackend backend)
=> (Connection -> IO ())	action to perform after connection is created
-> ConnectionString	Connection string to the database.
-> Int	Number of connections to be kept open in the pool.
-> m (Pool backend)

Same as createPostgresqlPool, but additionally takes a callback function for some connection-specific tweaking to be performed after connection creation. This could be used, for example, to change the schema. For more information, see:

https://groups.google.com/d/msg/yesodweb/qUXrEN_swEo/O0pFwqwQIdcJ

Since 2.1.3

module Database.Persist.Sql

type ConnectionString = ByteString Source #

A libpq connection string. A simple example of connection string would be "host=localhost port=5432 user=test dbname=test password=test". Please read libpq's documentation at http://www.postgresql.org/docs/9.1/static/libpq-connect.html for more details on how to create such strings.

data PostgresConf Source #

Information required to connect to a PostgreSQL database using persistent's generic facilities. These values are the same that are given to withPostgresqlPool.

Constructors

PostgresConf
Fields pgConnStr :: ConnectionString The connection string. pgPoolSize :: Int How many connections should be held on the connection pool.

Instances

Data PostgresConf Source #
Methods gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> PostgresConf -> c PostgresConf # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c PostgresConf # toConstr :: PostgresConf -> Constr # dataTypeOf :: PostgresConf -> DataType # dataCast1 :: Typeable (* -> ) t => (forall d. Data d => c (t d)) -> Maybe (c PostgresConf) # dataCast2 :: Typeable ( -> * -> *) t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c PostgresConf) # gmapT :: (forall b. Data b => b -> b) -> PostgresConf -> PostgresConf # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> PostgresConf -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> PostgresConf -> r # gmapQ :: (forall d. Data d => d -> u) -> PostgresConf -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> PostgresConf -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> PostgresConf -> m PostgresConf # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> PostgresConf -> m PostgresConf # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> PostgresConf -> m PostgresConf #
Read PostgresConf Source #
Methods readsPrec :: Int -> ReadS PostgresConf # readList :: ReadS [PostgresConf] # readPrec :: ReadPrec PostgresConf # readListPrec :: ReadPrec [PostgresConf] #
Show PostgresConf Source #
Methods showsPrec :: Int -> PostgresConf -> ShowS # show :: PostgresConf -> String # showList :: [PostgresConf] -> ShowS #
FromJSON PostgresConf Source #
Methods parseJSON :: Value -> Parser PostgresConf #
PersistConfig PostgresConf Source #
Associated Types type PersistConfigBackend PostgresConf :: (* -> ) -> -> * # type PersistConfigPool PostgresConf :: * # Methods loadConfig :: Value -> Parser PostgresConf # applyEnv :: PostgresConf -> IO PostgresConf # createPoolConfig :: PostgresConf -> IO (PersistConfigPool PostgresConf) # runPool :: (MonadBaseControl IO m, MonadIO m) => PostgresConf -> PersistConfigBackend PostgresConf m a -> PersistConfigPool PostgresConf -> m a #
type PersistConfigPool PostgresConf Source #
type PersistConfigPool PostgresConf = ConnectionPool
type PersistConfigBackend PostgresConf Source #
type PersistConfigBackend PostgresConf = SqlPersistT

openSimpleConn :: IsSqlBackend backend => LogFunc -> Connection -> IO backend Source #

Generate a Connection from a Connection

tableName :: PersistEntity record => record -> Text Source #

get the SQL string for the table that a PeristEntity represents Useful for raw SQL queries

fieldName :: PersistEntity record => EntityField record typ -> Text Source #

get the SQL string for the field that an EntityField represents Useful for raw SQL queries

mockMigration :: Migration -> IO () Source #

Mock a migration even when the database is not present. This function performs the same functionality of printMigration with the difference that an actualy database isn't needed for it.