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1. getBackendSpecificForeignKeyName :: BackendSpecificOverrides -> Maybe (EntityNameDB -> FieldNameDB -> ConstraintNameDB)

   persistent	Database.Persist.Sql

   If the override is defined, then this returns a function that accepts an entity name and field name and provides the ConstraintNameDB for the foreign key constraint. An abstract accessor for the BackendSpecificOverrides

2. setBackendSpecificForeignKeyName :: (EntityNameDB -> FieldNameDB -> ConstraintNameDB) -> BackendSpecificOverrides -> BackendSpecificOverrides

   persistent	Database.Persist.Sql

   Set the backend's foreign key generation function to this value.

3. runBefore :: SqlPoolHooks (m :: Type -> Type) backend -> backend -> Maybe IsolationLevel -> m ()

   persistent	Database.Persist.SqlBackend.Internal.SqlPoolHooks

   Run this action immediately before the action is performed.

4. getRunBefore :: SqlPoolHooks m backend -> backend -> Maybe IsolationLevel -> m ()

   persistent	Database.Persist.SqlBackend.SqlPoolHooks

   No documentation available.

5. modifyRunBefore :: SqlPoolHooks m backend -> ((backend -> Maybe IsolationLevel -> m ()) -> backend -> Maybe IsolationLevel -> m ()) -> SqlPoolHooks m backend

   persistent	Database.Persist.SqlBackend.SqlPoolHooks

   No documentation available.

6. setRunBefore :: SqlPoolHooks m backend -> (backend -> Maybe IsolationLevel -> m ()) -> SqlPoolHooks m backend

   persistent	Database.Persist.SqlBackend.SqlPoolHooks

   No documentation available.

7. PersistForeignConstraintUnmet :: Text -> PersistException

   persistent	Database.Persist.Types

   No documentation available.

8. class FromForm a

   http-api-data	Web.FormUrlEncoded

   Parse Form into a value. An example type and instance:

   data Person = Person
   { name :: String
   , age  :: Int }
   
   instance FromForm Person where
   fromForm f = Person
   <$> parseUnique "name" f
   <*> parseUnique "age"  f
   

   Instead of manually writing FromForm instances you can use a default generic implementation of fromForm. To do that, simply add deriving Generic clause to your datatype and declare a FromForm instance for your datatype without giving definition for fromForm. For instance, the previous example can be simplified into this:

   data Person = Person
   { name :: String
   , age  :: Int
   } deriving (Generic)
   
   instance FromForm Person
   

   The default implementation of fromForm is genericFromForm. It only works for records and it will use parseQueryParam for each field's value.

9. class FromFormKey k

   http-api-data	Web.FormUrlEncoded

   Typeclass for types that can be parsed from keys of a Form. This is the reverse of ToFormKey.

10. class ToForm a

    http-api-data	Web.FormUrlEncoded

    Convert a value into Form. An example type and instance:

    {-# LANGUAGE OverloadedLists #-}
    
    data Person = Person
    { name :: String
    , age  :: Int }
    
    instance ToForm Person where
    toForm person =
    [ ("name", toQueryParam (name person))
    , ("age", toQueryParam (age person)) ]
    

    Instead of manually writing ToForm instances you can use a default generic implementation of toForm. To do that, simply add deriving Generic clause to your datatype and declare a ToForm instance for your datatype without giving definition for toForm. For instance, the previous example can be simplified into this:

    data Person = Person
    { name :: String
    , age  :: Int
    } deriving (Generic)
    
    instance ToForm Person
    

    The default implementation of toForm is genericToForm.

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