napkin-0.5.11
Safe HaskellNone
LanguageHaskell2010

Napkin.Run.Effects.Languages.SqlRead

Synopsis

Documentation

data SqlRead m a where #

Instances

Instances details
GShow (SqlRead a :: Type -> Type) # 
Instance details

Defined in Napkin.Run.Effects.Languages.SqlRead

Methods

gshowsPrec :: forall (a0 :: k). Int -> SqlRead a a0 -> ShowS #

Eq (SqlRead a b) # 
Instance details

Defined in Napkin.Run.Effects.Languages.SqlRead

Methods

(==) :: SqlRead a b -> SqlRead a b -> Bool #

(/=) :: SqlRead a b -> SqlRead a b -> Bool #

Show (SqlRead a b) # 
Instance details

Defined in Napkin.Run.Effects.Languages.SqlRead

Methods

showsPrec :: Int -> SqlRead a b -> ShowS #

show :: SqlRead a b -> String #

showList :: [SqlRead a b] -> ShowS #

runQuerySingleAnswer :: forall a r. (Val a, Member SqlRead r) => Query -> Sem r (Maybe a) #

Run a query and pull out the first column from its first row. Meant for queries that return a single result.