Copyright | 2014 Kei Hibino |
---|---|
License | BSD3 |
Maintainer | ex8k.hibino@gmail.com |
Stability | experimental |
Portability | unknown |
Safe Haskell | None |
Language | Haskell2010 |
This module is documentation module for relational record.
- query :: (MonadQualify ConfigureQuery m, MonadQuery m) => Relation () r -> m (Projection Flat r)
- queryMaybe :: (MonadQualify ConfigureQuery m, MonadQuery m) => Relation () r -> m (Projection Flat (Maybe r))
- on :: MonadQuery m => Projection Flat (Maybe Bool) -> m ()
- wheres :: MonadRestrict Flat m => Projection Flat (Maybe Bool) -> m ()
- groupBy :: MonadAggregate m => forall r. Projection Flat r -> m (Projection Aggregated r)
- having :: MonadRestrict Aggregated m => Projection Aggregated (Maybe Bool) -> m ()
- distinct :: MonadQuery m => m ()
- all' :: MonadQuery m => m ()
- (<-#) :: Monad m => AssignTarget r v -> Projection Flat v -> Assignings r m ()
- inner :: Relation () a -> Relation () b -> [JoinRestriction a b] -> Relation () (a, b)
- left :: Relation () a -> Relation () b -> [JoinRestriction a (Maybe b)] -> Relation () (a, Maybe b)
- right :: Relation () a -> Relation () b -> [JoinRestriction (Maybe a) b] -> Relation () (Maybe a, b)
- full :: Relation () a -> Relation () b -> [JoinRestriction (Maybe a) (Maybe b)] -> Relation () (Maybe a, Maybe b)
- on' :: ([JoinRestriction a b] -> Relation pc (a, b)) -> [JoinRestriction a b] -> Relation pc (a, b)
- data Relation p r :: * -> * -> *
- relation :: QuerySimple (Projection Flat r) -> Relation () r
- aggregateRelation :: QueryAggregate (Projection Aggregated r) -> Relation () r
- data UpdateTarget p r :: * -> * -> *
- updateTarget :: AssignStatement r () -> UpdateTarget () r
- data Restriction p r :: * -> * -> *
- restriction :: RestrictedStatement r () -> Restriction () r
- data Projection c t :: * -> * -> *
- data Flat :: *
- data Aggregated :: *
- data Exists :: *
- data OverWindow :: *
- data Pi r0 r1 :: * -> * -> *
- (!) :: Projection c a -> Pi a b -> Projection c b
- (<.>) :: Pi a b -> Pi b c -> Pi a c
- value :: (ShowConstantTermsSQL t, OperatorProjectable p) => t -> p t
- values :: (ShowConstantTermsSQL t, OperatorProjectable p) => [t] -> ListProjection p t
- (.=.) :: (OperatorProjectable p, ProjectableShowSql p) => p ft -> p ft -> p (Maybe Bool)
- (.<.) :: (OperatorProjectable p, ProjectableShowSql p) => p ft -> p ft -> p (Maybe Bool)
- (.<=.) :: (OperatorProjectable p, ProjectableShowSql p) => p ft -> p ft -> p (Maybe Bool)
- (.>.) :: (OperatorProjectable p, ProjectableShowSql p) => p ft -> p ft -> p (Maybe Bool)
- (.>=.) :: (OperatorProjectable p, ProjectableShowSql p) => p ft -> p ft -> p (Maybe Bool)
- (.<>.) :: (OperatorProjectable p, ProjectableShowSql p) => p ft -> p ft -> p (Maybe Bool)
- and' :: (OperatorProjectable p, ProjectableShowSql p) => p (Maybe Bool) -> p (Maybe Bool) -> p (Maybe Bool)
- or' :: (OperatorProjectable p, ProjectableShowSql p) => p (Maybe Bool) -> p (Maybe Bool) -> p (Maybe Bool)
- in' :: (OperatorProjectable p, ProjectableShowSql p) => p t -> ListProjection p t -> p (Maybe Bool)
- (.||.) :: (OperatorProjectable p, ProjectableShowSql p, IsString a) => p a -> p a -> p a
- like :: (OperatorProjectable p, ProjectableShowSql p, IsString a, ShowConstantTermsSQL a) => p a -> a -> p (Maybe Bool)
- like' :: (OperatorProjectable p, ProjectableShowSql p, IsString a) => p a -> p a -> p (Maybe Bool)
- (.+.) :: (OperatorProjectable p, ProjectableShowSql p, Num a) => p a -> p a -> p a
- (.-.) :: (OperatorProjectable p, ProjectableShowSql p, Num a) => p a -> p a -> p a
- (.*.) :: (OperatorProjectable p, ProjectableShowSql p, Num a) => p a -> p a -> p a
- (./.) :: (OperatorProjectable p, ProjectableShowSql p, Num a) => p a -> p a -> p a
- isNothing :: (OperatorProjectable (Projection c), ProjectableShowSql (Projection c), HasColumnConstraint NotNull r) => Projection c (Maybe r) -> Projection c (Maybe Bool)
- isJust :: (OperatorProjectable (Projection c), ProjectableShowSql (Projection c), HasColumnConstraint NotNull r) => Projection c (Maybe r) -> Projection c (Maybe Bool)
- fromMaybe :: (OperatorProjectable (Projection c), ProjectableShowSql (Projection c), HasColumnConstraint NotNull r) => Projection c r -> Projection c (Maybe r) -> Projection c r
- not' :: (OperatorProjectable p, ProjectableShowSql p) => p (Maybe Bool) -> p (Maybe Bool)
- exists :: (OperatorProjectable p, ProjectableShowSql p) => ListProjection (Projection Exists) r -> p (Maybe Bool)
- negate' :: (OperatorProjectable p, ProjectableShowSql p, Num a) => p a -> p a
- fromIntegral' :: (SqlProjectable p, ProjectableShowSql p, Integral a, Num b) => p a -> p b
- showNum :: (SqlProjectable p, ProjectableShowSql p, Num a, IsString b) => p a -> p b
- casesOrElse :: (OperatorProjectable p, ProjectableShowSql p) => [(p (Maybe Bool), p a)] -> p a -> p a
- case' :: (OperatorProjectable p, ProjectableShowSql p) => p a -> [(p a, p b)] -> p b -> p b
- count :: (Integral b, AggregatedContext ac, SqlProjectable (p ac)) => Projection Flat a -> p ac b
- sum' :: (Num a, AggregatedContext ac, SqlProjectable (p ac)) => Projection Flat a -> p ac (Maybe a)
- avg :: (Num a, Fractional b, AggregatedContext ac, SqlProjectable (p ac)) => Projection Flat a -> p ac (Maybe b)
- max' :: (Ord a, AggregatedContext ac, SqlProjectable (p ac)) => Projection Flat a -> p ac (Maybe a)
- min' :: (Ord a, AggregatedContext ac, SqlProjectable (p ac)) => Projection Flat a -> p ac (Maybe a)
- every :: (AggregatedContext ac, SqlProjectable (p ac)) => Projection Flat (Maybe Bool) -> p ac (Maybe Bool)
- any' :: (AggregatedContext ac, SqlProjectable (p ac)) => Projection Flat (Maybe Bool) -> p ac (Maybe Bool)
- some' :: (AggregatedContext ac, SqlProjectable (p ac)) => Projection Flat (Maybe Bool) -> p ac (Maybe Bool)
- over :: SqlProjectable (Projection c) => Projection OverWindow a -> Window c () -> Projection c a
- rank :: Integral a => Projection OverWindow a
- denseRank :: Integral a => Projection OverWindow a
- rowNumber :: Integral a => Projection OverWindow a
- percentRank :: Projection OverWindow Double
- cumeDist :: Projection OverWindow Double
- union :: Relation () a -> Relation () a -> Relation () a
- except :: Relation () a -> Relation () a -> Relation () a
- intersect :: Relation () a -> Relation () a -> Relation () a
- just :: ProjectableMaybe p => forall a. p a -> p (Maybe a)
- flattenMaybe :: ProjectableMaybe p => forall a. p (Maybe (Maybe a)) -> p (Maybe a)
- (?!) :: Projection c (Maybe a) -> Pi a b -> Projection c (Maybe b)
- (?!?) :: Projection c (Maybe a) -> Pi a (Maybe b) -> Projection c (Maybe b)
- (<?.>) :: Pi a (Maybe b) -> Pi b c -> Pi a (Maybe c)
- (<?.?>) :: Pi a (Maybe b) -> Pi b (Maybe c) -> Pi a (Maybe c)
- (?+?) :: (OperatorProjectable p, ProjectableShowSql p, Num a) => p (Maybe a) -> p (Maybe a) -> p (Maybe a)
- negateMaybe :: (OperatorProjectable p, ProjectableShowSql p, Num a) => p (Maybe a) -> p (Maybe a)
- sumMaybe :: (Num a, AggregatedContext ac, SqlProjectable (p ac)) => Projection Flat (Maybe a) -> p ac (Maybe a)
- query' :: MonadQuery m => forall p r. Relation p r -> m (PlaceHolders p, Projection Flat r)
- left' :: Relation pa a -> Relation pb b -> [JoinRestriction a (Maybe b)] -> Relation (pa, pb) (a, Maybe b)
- relation' :: SimpleQuery p r -> Relation p r
- updateTarget' :: AssignStatement r (PlaceHolders p) -> UpdateTarget p r
- restriction' :: RestrictedStatement r (PlaceHolders p) -> Restriction p r
- union' :: Relation p a -> Relation q a -> Relation (p, q) a
- class ProductConstructor r
- class ProjectableFunctor p where
- (|$|) :: ProductConstructor (a -> b) => (a -> b) -> p a -> p b
- class ProjectableFunctor p => ProjectableApplicative p where
- (|*|) :: p (a -> b) -> p a -> p b
- (><) :: ProjectableApplicative p => p a -> p b -> p (a, b)
- relationalQuery :: Relation p r -> Query p r
- typedInsert :: Table r -> Pi r r' -> Insert r'
- typedInsertQuery :: Table r -> Pi r r' -> Relation p r' -> InsertQuery p
- typedUpdate :: Table r -> UpdateTarget p r -> Update p
- typedDelete :: Table r -> Restriction p r -> Delete p
- typedKeyUpdate :: Table a -> Pi a p -> KeyUpdate p a
- derivedInsert :: TableDerivable r => Pi r r' -> Insert r'
- derivedInsertQuery :: TableDerivable r => Pi r r' -> Relation p r' -> InsertQuery p
- derivedUpdate :: TableDerivable r => AssignStatement r (PlaceHolders p) -> Update p
- derivedDelete :: TableDerivable r => RestrictedStatement r (PlaceHolders p) -> Delete p
- prepareNoFetch :: (UntypeableNoFetch s, IConnection conn) => conn -> s p -> IO (PreparedStatement p ())
- bind :: ToSql SqlValue p => PreparedStatement p a -> p -> BoundStatement a
- execute :: BoundStatement a -> IO (ExecutedStatement a)
- executeNoFetch :: BoundStatement () -> IO Integer
- prepareQuery :: IConnection conn => conn -> Query p a -> IO (PreparedQuery p a)
- fetch :: FromSql SqlValue a => ExecutedStatement a -> IO (Maybe a)
- runQuery :: (IConnection conn, ToSql SqlValue p, FromSql SqlValue a) => conn -> Query p a -> p -> IO [a]
- prepareInsert :: IConnection conn => conn -> Insert a -> IO (PreparedInsert a)
- runInsert :: (IConnection conn, ToSql SqlValue a) => conn -> Insert a -> a -> IO Integer
- prepareInsertQuery :: IConnection conn => conn -> InsertQuery p -> IO (PreparedInsertQuery p)
- runInsertQuery :: (IConnection conn, ToSql SqlValue p) => conn -> InsertQuery p -> p -> IO Integer
- prepareUpdate :: IConnection conn => conn -> Update p -> IO (PreparedUpdate p)
- runUpdate :: (IConnection conn, ToSql SqlValue p) => conn -> Update p -> p -> IO Integer
- prepareDelete :: IConnection conn => conn -> Delete p -> IO (PreparedDelete p)
- runDelete :: (IConnection conn, ToSql SqlValue p) => conn -> Delete p -> p -> IO Integer
- prepareKeyUpdate :: IConnection conn => conn -> KeyUpdate p a -> IO (PreparedKeyUpdate p a)
- bindKeyUpdate :: ToSql SqlValue a => PreparedKeyUpdate p a -> a -> BoundStatement ()
- runKeyUpdate :: (IConnection conn, ToSql SqlValue a) => conn -> KeyUpdate p a -> a -> IO Integer
Concepts
User interface of Relational Record has main two part of modules.
Database.Relational.Query
- Relational Query Building DSL
Database.HDBC.Record
- Database Operation Actions
Relational Query Building DSL
Relational Query (Database.Relational.Query) module defines Typed DSL to build complex SQL query.
Monadic Query Context Building
On building query, query structures can be accumulated in monadic context.
Monadic Operators
Some operators are defined to build query structures in monadic context.
query
and queryMaybe
operators grow query product of monadic context like join operation of SQL.
on
operator appends a new condition into recent join product condition.
groupBy
operator aggregates flat projection value, and can be used only in MonadAggregate
context.
wheres
and having
operators appends a new condition into whole query condition.
having
only accepts aggregated projection value, and can be used only in MonadRestrict
Aggregated
context.
distinct
operator and all'
operator specify SELECT DISTINCT or SELECT ALL, the last specified in monad is used.
'(<-#)' operator assigns update target column and projection value to build update statement structure.
query :: (MonadQualify ConfigureQuery m, MonadQuery m) => Relation () r -> m (Projection Flat r)
Join sub-query. Query result is not Maybe
.
queryMaybe :: (MonadQualify ConfigureQuery m, MonadQuery m) => Relation () r -> m (Projection Flat (Maybe r))
Join sub-query. Query result is Maybe
.
The combinations of query
and queryMaybe
express
inner joins, left outer joins, right outer joins, and full outer joins.
Here is an example of a right outer join:
outerJoin = relation $ do e <- queryMaybe employee d <- query department on $ e ?! E.deptId' .=. just (d ! D.deptId') return $ (,) |$| e |*| d
on :: MonadQuery m => Projection Flat (Maybe Bool) -> m ()
Add restriction to last join. Projection type version.
wheres :: MonadRestrict Flat m => Projection Flat (Maybe Bool) -> m ()
Add restriction to this not aggregated query.
:: forall (m :: * -> *). MonadAggregate m | |
=> Projection Flat r | Projection to add into group by |
-> m (Projection Aggregated r) | Result context and aggregated projection | Add GROUP BY term into context and get aggregated projection. Non-traditional group-by version. |
Add GROUP BY term into context and get aggregated projection.
having :: MonadRestrict Aggregated m => Projection Aggregated (Maybe Bool) -> m ()
Add restriction to this aggregated query. Aggregated Projection type version.
distinct :: MonadQuery m => m ()
Specify DISTINCT attribute to query context.
all' :: MonadQuery m => m ()
Specify ALL attribute to query context.
(<-#) :: Monad m => AssignTarget r v -> Projection Flat v -> Assignings r m () infix 4
Add and assginment.
Direct Join Operators
Not monadic style join is supported by some direct join operators.
inner
, left
, right
, full
operators can construct join products directly like SQL.
inner
operator is INNER JOIN of SQL, left
operator is LEFT OUTER JOIN of SQL, and so on.
on'
operator specifies condition of join product.
inner infixl 8
:: Relation () a | Left query to join |
-> Relation () b | Right query to join |
-> [JoinRestriction a b] | Join restrictions |
-> Relation () (a, b) | Result joined relation |
Direct inner join.
left infixl 8
:: Relation () a | Left query to join |
-> Relation () b | Right query to join |
-> [JoinRestriction a (Maybe b)] | Join restrictions |
-> Relation () (a, Maybe b) | Result joined relation |
Direct left outer join.
right infixl 8
:: Relation () a | Left query to join |
-> Relation () b | Right query to join |
-> [JoinRestriction (Maybe a) b] | Join restrictions |
-> Relation () (Maybe a, b) | Result joined relation |
Direct right outer join.
full infixl 8
:: Relation () a | Left query to join |
-> Relation () b | Right query to join |
-> [JoinRestriction (Maybe a) (Maybe b)] | Join restrictions |
-> Relation () (Maybe a, Maybe b) | Result joined relation |
Direct full outer join.
on' :: ([JoinRestriction a b] -> Relation pc (a, b)) -> [JoinRestriction a b] -> Relation pc (a, b) infixl 8
Apply restriction for direct join style.
Finalize Context
Several operators are defined to make Relation
type with finalizing query monadic context.
relation
operator finalizes flat (not aggregated) query monadic context,
and aggregateRelation
operator finalizes aggregated query monadic context.
Both operator convert monadic context into Relation
type,
and finalized Relation
can be reused as joining and sub-querying in another queries.
updateTarget
operator finalize monadic context into UpdateTarget
type
which can be used as update statement.
restriction
operator finalize monadic context into Restriction
type
which can be used as delete statement.
data Relation p r :: * -> * -> *
Relation type with place-holder parameter p
and query result type r
.
relation :: QuerySimple (Projection Flat r) -> Relation () r
Finalize QuerySimple
monad and generate Relation
.
aggregateRelation :: QueryAggregate (Projection Aggregated r) -> Relation () r
Finalize QueryAggregate
monad and geneate Relation
.
data UpdateTarget p r :: * -> * -> *
UpdateTarget type with place-holder parameter p
and projection record type r
.
TableDerivable r => Show (UpdateTarget p r) |
updateTarget :: AssignStatement r () -> UpdateTarget () r
Finalize Target
monad and generate UpdateTarget
.
data Restriction p r :: * -> * -> *
Restriction type with place-holder parameter p
and projection record type r
.
TableDerivable r => Show (Restriction p r) | Show where clause. |
restriction :: RestrictedStatement r () -> Restriction () r
Finalize Restrict
monad and generate Restriction
.
Projection
SQL expression can be projected to Haskell phantom type in this DSL.
Projection Type
Projection
c t is SQL value type projection to Haskell type with context type c correspond Haskell type t.
Flat
is not aggregated query context type,
Aggregated
is aggregated query context type,
OverWindow
is window function context type, and so on.
Module Database.Relational.Query.Context contains documentation of other context types.
data Projection c t :: * -> * -> *
Phantom typed projection. Projected into Haskell record type t
.
OperatorProjectable (Projection Flat) | |
OperatorProjectable (Projection Aggregated) | |
SqlProjectable (Projection Flat) | Unsafely make |
SqlProjectable (Projection Aggregated) | Unsafely make |
SqlProjectable (Projection OverWindow) | Unsafely make |
ProjectableShowSql (Projection c) | Unsafely get SQL term from |
ProjectableMaybe (Projection c) | Control phantom |
ProjectableFunctor (Projection c) | Compose seed of record type |
ProjectableApplicative (Projection c) | Compose record type |
Show (Projection c t) |
data Flat :: *
Type tag for flat (not-aggregated) query
OperatorProjectable (Projection Flat) | |
SqlProjectable (Projection Flat) | Unsafely make |
data Aggregated :: *
Type tag for aggregated query
AggregatedContext Aggregated | |
OperatorProjectable (Projection Aggregated) | |
SqlProjectable (Projection Aggregated) | Unsafely make |
data Exists :: *
Type tag for exists predicate
data OverWindow :: *
Type tag for window function building
AggregatedContext OverWindow | |
SqlProjectable (Projection OverWindow) | Unsafely make |
Projection Path
!
operator is projected value selector using projection path type Pi
r0 r1.
Pi
r0 r1 is projection path type selecting column type r1 from record type r0.
<.>
operator makes composed projection path from two projection paths.
data Pi r0 r1 :: * -> * -> *
Projection path from type r0
into type r1
.
This type also indicate key object which type is r1
for record type r0
.
ProjectableFunctor (Pi a) | Compose seed of projection path |
ProjectableApplicative (Pi a) | Compose projection path |
(!) infixl 8
:: Projection c a | Source projection |
-> Pi a b | Projection path |
-> Projection c b | Narrower projected object |
Get narrower projection along with projection path.
Projection Operators
Some operators are defined to calculate projected values.
For example,
value
operator projects from Haskell value into Projection
corresponding SQL value,
values
operator projects from Haskell list value into ListProjection
, corresponding SQL set value,
.=.
operator is equal compare operation of projected value correspond to SQL =,
.+.
operator is plus operation of projected value correspond to SQL +, and so on.
Module Database.Relational.Query.Projectable contains documentation of other projection operators.
value :: (ShowConstantTermsSQL t, OperatorProjectable p) => t -> p t
Generate polymorphic projection of SQL constant values from Haskell value.
values :: (ShowConstantTermsSQL t, OperatorProjectable p) => [t] -> ListProjection p t
Polymorphic proejction of SQL set value from Haskell list.
(.=.) :: (OperatorProjectable p, ProjectableShowSql p) => p ft -> p ft -> p (Maybe Bool) infix 4
Compare operator corresponding SQL = .
(.<.) :: (OperatorProjectable p, ProjectableShowSql p) => p ft -> p ft -> p (Maybe Bool) infix 4
Compare operator corresponding SQL < .
(.<=.) :: (OperatorProjectable p, ProjectableShowSql p) => p ft -> p ft -> p (Maybe Bool) infix 4
Compare operator corresponding SQL <= .
(.>.) :: (OperatorProjectable p, ProjectableShowSql p) => p ft -> p ft -> p (Maybe Bool) infix 4
Compare operator corresponding SQL > .
(.>=.) :: (OperatorProjectable p, ProjectableShowSql p) => p ft -> p ft -> p (Maybe Bool) infix 4
Compare operator corresponding SQL >= .
(.<>.) :: (OperatorProjectable p, ProjectableShowSql p) => p ft -> p ft -> p (Maybe Bool) infix 4
Compare operator corresponding SQL <> .
and' :: (OperatorProjectable p, ProjectableShowSql p) => p (Maybe Bool) -> p (Maybe Bool) -> p (Maybe Bool) infixr 3
Logical operator corresponding SQL AND .
or' :: (OperatorProjectable p, ProjectableShowSql p) => p (Maybe Bool) -> p (Maybe Bool) -> p (Maybe Bool) infixr 2
Logical operator corresponding SQL OR .
in' :: (OperatorProjectable p, ProjectableShowSql p) => p t -> ListProjection p t -> p (Maybe Bool) infix 4
Binary operator corresponding SQL IN .
(.||.) :: (OperatorProjectable p, ProjectableShowSql p, IsString a) => p a -> p a -> p a infixl 5
Concatinate operator corresponding SQL || .
like :: (OperatorProjectable p, ProjectableShowSql p, IsString a, ShowConstantTermsSQL a) => p a -> a -> p (Maybe Bool) infix 4
String-compare operator corresponding SQL LIKE .
like' :: (OperatorProjectable p, ProjectableShowSql p, IsString a) => p a -> p a -> p (Maybe Bool) infix 4
String-compare operator corresponding SQL LIKE .
(.+.) :: (OperatorProjectable p, ProjectableShowSql p, Num a) => p a -> p a -> p a infixl 6
Number operator corresponding SQL + .
(.-.) :: (OperatorProjectable p, ProjectableShowSql p, Num a) => p a -> p a -> p a infixl 6
Number operator corresponding SQL - .
(.*.) :: (OperatorProjectable p, ProjectableShowSql p, Num a) => p a -> p a -> p a infixl 7
Number operator corresponding SQL * .
(./.) :: (OperatorProjectable p, ProjectableShowSql p, Num a) => p a -> p a -> p a infixl 7
Number operator corresponding SQL /// .
isNothing :: (OperatorProjectable (Projection c), ProjectableShowSql (Projection c), HasColumnConstraint NotNull r) => Projection c (Maybe r) -> Projection c (Maybe Bool)
Operator corresponding SQL IS NULL , and extended against record types.
isJust :: (OperatorProjectable (Projection c), ProjectableShowSql (Projection c), HasColumnConstraint NotNull r) => Projection c (Maybe r) -> Projection c (Maybe Bool)
Operator corresponding SQL NOT (... IS NULL) , and extended against record type.
fromMaybe :: (OperatorProjectable (Projection c), ProjectableShowSql (Projection c), HasColumnConstraint NotNull r) => Projection c r -> Projection c (Maybe r) -> Projection c r
Operator from maybe type using record extended isNull
.
not' :: (OperatorProjectable p, ProjectableShowSql p) => p (Maybe Bool) -> p (Maybe Bool)
Logical operator corresponding SQL NOT .
exists :: (OperatorProjectable p, ProjectableShowSql p) => ListProjection (Projection Exists) r -> p (Maybe Bool)
Logical operator corresponding SQL EXISTS .
negate' :: (OperatorProjectable p, ProjectableShowSql p, Num a) => p a -> p a
Number negate uni-operator corresponding SQL -.
fromIntegral' :: (SqlProjectable p, ProjectableShowSql p, Integral a, Num b) => p a -> p b
Number fromIntegral uni-operator.
showNum :: (SqlProjectable p, ProjectableShowSql p, Num a, IsString b) => p a -> p b
Unsafely show number into string-like type in projections.
:: forall (p :: * -> *). (OperatorProjectable p, ProjectableShowSql p) | |
=> [(p (Maybe Bool), p a)] | Each when clauses |
-> p a | Else result projection |
-> p a | Result projection |
Same as caseSearch
, but you can write like list casesOrElse
clause.
:: forall (p :: * -> *). (OperatorProjectable p, ProjectableShowSql p) | |
=> p a | Projection value to match |
-> [(p a, p b)] | Each when clauses |
-> p b | Else result projection |
-> p b | Result projection |
Simple case operator correnponding SQL simple CASE. Like, CASE x WHEN v THEN a WHEN w THEN b ... ELSE c END
Aggregate and Window Functions
Typed aggregate function operators are defined. Aggregated value types is distinguished with Flat value types.
For example,
sum'
operator is aggregate function of projected flat (not aggregated) value
correspond to SQL SUM(...),
rank
operator is window function of projected value correspond to SQL RANK(), and so on.
To convert window function result into normal projection, use the over
operator with built Window
monad.
Module Database.Relational.Query.Projectable contains documentation of other aggregate function operators and window function operators.
count :: (Integral b, AggregatedContext ac, SqlProjectable (p ac)) => Projection Flat a -> p ac b
Aggregation function COUNT.
sum' :: (Num a, AggregatedContext ac, SqlProjectable (p ac)) => Projection Flat a -> p ac (Maybe a)
Aggregation function SUM.
avg :: (Num a, Fractional b, AggregatedContext ac, SqlProjectable (p ac)) => Projection Flat a -> p ac (Maybe b)
Aggregation function AVG.
max' :: (Ord a, AggregatedContext ac, SqlProjectable (p ac)) => Projection Flat a -> p ac (Maybe a)
Aggregation function MAX.
min' :: (Ord a, AggregatedContext ac, SqlProjectable (p ac)) => Projection Flat a -> p ac (Maybe a)
Aggregation function MIN.
every :: (AggregatedContext ac, SqlProjectable (p ac)) => Projection Flat (Maybe Bool) -> p ac (Maybe Bool)
Aggregation function EVERY.
any' :: (AggregatedContext ac, SqlProjectable (p ac)) => Projection Flat (Maybe Bool) -> p ac (Maybe Bool)
Aggregation function ANY.
some' :: (AggregatedContext ac, SqlProjectable (p ac)) => Projection Flat (Maybe Bool) -> p ac (Maybe Bool)
Aggregation function SOME.
over :: SqlProjectable (Projection c) => Projection OverWindow a -> Window c () -> Projection c a infix 8
Operator to make window function result projection using built Window
monad.
rank :: Integral a => Projection OverWindow a
RANK() term.
denseRank :: Integral a => Projection OverWindow a
DENSE_RANK() term.
rowNumber :: Integral a => Projection OverWindow a
ROW_NUMBER() term.
percentRank :: Projection OverWindow Double
PERCENT_RANK() term.
cumeDist :: Projection OverWindow Double
CUME_DIST() term.
Set Operators
Several operators are defined to manipulate relation set.
union
operator makes union relation set of two relation set correspond to SQL UNION.
except
operator makes difference relation set of two relation set correspond to SQL EXCEPT.
intersect
operator makes intersection relation set of two relation set correspond to SQL INTERSECT.
Maybe Projections
Some operators are provided to manage projections with Maybe
phantom type.
just
operator creates Maybe
typed projection,
flattenMaybe
operator joins nested Maybe
typed projection.
Maybe
type flavor of operators against projection path, projection and aggregation are also provided.
For example,
?!
operator is maybe flavor of !
,
<?.>
operator is maybe flavor of <.>
.
?!?
operator and <?.?>
operator join
two Maybe
phantom functors.
?+?
operator is maybe flavor of .+.
,
negateMaybe
operator is maybe flavor of negate'
,
sumMaybe
operator is maybe flavor of sum'
.
Module Database.Relational.Query.Projectable and Database.Relational.Query.ProjectableExtended
contain documentation of other Maybe
flavor projection operators.
just :: ProjectableMaybe p => forall a. p a -> p (Maybe a)
Cast projection phantom type into Maybe
.
flattenMaybe :: ProjectableMaybe p => forall a. p (Maybe (Maybe a)) -> p (Maybe a)
Compose nested Maybe
phantom type on projection.
(?!) infixl 8
:: Projection c (Maybe a) | Source |
-> Pi a b | Projection path |
-> Projection c (Maybe b) | Narrower projected object. |
(?!?) infixl 8
:: Projection c (Maybe a) | Source |
-> Pi a (Maybe b) | Projection path. |
-> Projection c (Maybe b) | Narrower projected object. |
(<?.?>) :: Pi a (Maybe b) -> Pi b (Maybe c) -> Pi a (Maybe c) infixl 8
Compose projection path. Maybe
phantom functors are join
-ed like >=>
.
(?+?) :: (OperatorProjectable p, ProjectableShowSql p, Num a) => p (Maybe a) -> p (Maybe a) -> p (Maybe a) infixl 6
Number operator corresponding SQL + .
negateMaybe :: (OperatorProjectable p, ProjectableShowSql p, Num a) => p (Maybe a) -> p (Maybe a)
Number negate uni-operator corresponding SQL -.
sumMaybe :: (Num a, AggregatedContext ac, SqlProjectable (p ac)) => Projection Flat (Maybe a) -> p ac (Maybe a)
Aggregation function SUM.
Placeholders
Placeholders' flavor of operators against query operation and set operation are also provided, to realize type safe placeholders.
query'
, left'
, relation'
, updateTarget'
, restriction'
, and union'
operator are placeholders' flavor query
, left
, relation
, updateTarget
, restriction
and union
.
Module Database.Relational.Query.Relation and Database.Relational.Query.Effect contains documentation of other placeholders' flavor operators.
query' :: MonadQuery m => forall p r. Relation p r -> m (PlaceHolders p, Projection Flat r)
Join sub-query with place-holder parameter p
. query result is not Maybe
.
left' infixl 8
:: Relation pa a | Left query to join |
-> Relation pb b | Right query to join |
-> [JoinRestriction a (Maybe b)] | Join restrictions |
-> Relation (pa, pb) (a, Maybe b) | Result joined relation |
Direct left outer join with place-holder parameters.
relation' :: SimpleQuery p r -> Relation p r
Finalize QuerySimple
monad and generate Relation
with place-holder parameter p
.
updateTarget' :: AssignStatement r (PlaceHolders p) -> UpdateTarget p r
Finalize Target
monad and generate UpdateTarget
with place-holder parameter p
.
restriction' :: RestrictedStatement r (PlaceHolders p) -> Restriction p r
Finalize Restrict
monad and generate Restriction
with place-holder parameter p
union' :: Relation p a -> Relation q a -> Relation (p, q) a infixl 7
Union of two relations with place-holder parameters.
Record Mapping
Applicative style record mapping is supported, for Projection
, Pi
and PlaceHolders
.
|$|
operator can be used on ProjectableFunctor
context, and
|*|
operator can be used on ProjectableApplicative
context with ProductConstructor
,
like Foo |$| projection1 |*| projection2 |*| projection3
, Foo |$| placeholders1 |*| placeholders2 |*| placeholders3, and so on.
><
operator constructs pair result. x >< y is the same as (,) |$| x |*| y.
class ProductConstructor r
Specify tuple like record constructors which are allowed to define ProjectableFunctor
.
ProductConstructor (a -> b -> (a, b)) | ProductConstructor instance of pair. |
class ProjectableFunctor p where
Weaken functor on projections.
(|$|) :: ProductConstructor (a -> b) => (a -> b) -> p a -> p b infixl 4
Method like fmap
.
ProjectableFunctor PlaceHolders | Compose seed of record type |
ProjectableFunctor (Projection c) | Compose seed of record type |
ProjectableFunctor (Pi a) | Compose seed of projection path |
class ProjectableFunctor p => ProjectableApplicative p where
Weaken applicative functor on projections.
ProjectableApplicative PlaceHolders | Compose record type |
ProjectableApplicative (Projection c) | Compose record type |
ProjectableApplicative (Pi a) | Compose projection path |
(><) :: ProjectableApplicative p => p a -> p b -> p (a, b) infixl 1
Binary operator the same as projectZip
.
Database Statements
Some functions are defined to expand query structure into flat SQL statements to be used by database operation.
relationalQuery
function converts Relation
type info flat SQL query like SELECT statement.
typedInsert
function converts Pi
key type info flat SQL INSERT statement.
typedInsertQuery
function converts Pi
key type and Relation
type info flat SQL INSERT ... SELECT ... statement.
typedUpdate
function converts UpdateTarget
type into flat SQL UPDATE statement.
typedDelete
function converts Restriction
into flat SQL DELETE statement.
typedKeyUpdate
function converts Pi
key type info flat SQL UPDATE statement.
Some handy table type inferred functions are provided,
derivedInsert
, derivedInsertQuery
, derivedUpdate
and derivedDelete
.
relationalQuery :: Relation p r -> Query p r
typedInsertQuery :: Table r -> Pi r r' -> Relation p r' -> InsertQuery p
Make typed InsertQuery
from columns selector Table
, Pi
and Relation
.
typedUpdate :: Table r -> UpdateTarget p r -> Update p
Make typed Update
using defaultConfig
, Table
and UpdateTarget
.
typedDelete :: Table r -> Restriction p r -> Delete p
Make typed Delete
from Table
and Restriction
.
typedKeyUpdate :: Table a -> Pi a p -> KeyUpdate p a
derivedInsert :: TableDerivable r => Pi r r' -> Insert r'
Table type inferred Insert
.
derivedInsertQuery :: TableDerivable r => Pi r r' -> Relation p r' -> InsertQuery p
Table type inferred InsertQuery
.
derivedUpdate :: TableDerivable r => AssignStatement r (PlaceHolders p) -> Update p
Make typed Update
from defaultConfig
, derived table and AssignStatement
derivedDelete :: TableDerivable r => RestrictedStatement r (PlaceHolders p) -> Delete p
Make typed Delete
from defaultConfig
, derived table and RestrictContext
Database Operations
Some HDBC actions are defined for database side effects.
Generalized Statement
Actions to manage generalized SQL statements.
prepareNoFetch :: (UntypeableNoFetch s, IConnection conn) => conn -> s p -> IO (PreparedStatement p ())
Generalized prepare inferred from UntypeableNoFetch
instance.
bind :: ToSql SqlValue p => PreparedStatement p a -> p -> BoundStatement a
Typed operation to bind parameters. Infered RecordToSql
is used.
execute :: BoundStatement a -> IO (ExecutedStatement a)
Typed execute operation.
executeNoFetch :: BoundStatement () -> IO Integer
Typed execute operation. Only get result.
Select
Actions to manage SELECT statements.
:: IConnection conn | |
=> conn | Database connection |
-> Query p a | Typed query |
-> IO (PreparedQuery p a) | Result typed prepared query with parameter type |
Same as prepare
.
:: (IConnection conn, ToSql SqlValue p, FromSql SqlValue a) | |
=> conn | Database connection |
-> Query p a | Query to get record type |
-> p | Parameter type |
-> IO [a] | Action to get records |
Prepare SQL, bind parameters, execute statement and lazily fetch all records.
Insert Values
Actions to manage INSERT ... VALUES ... statements.
prepareInsert :: IConnection conn => conn -> Insert a -> IO (PreparedInsert a)
Same as prepare
.
runInsert :: (IConnection conn, ToSql SqlValue a) => conn -> Insert a -> a -> IO Integer
Prepare insert statement, bind parameters, execute statement and get execution result.
Insert Select Results
Actions to manage INSERT ... SELECT ... statements.
prepareInsertQuery :: IConnection conn => conn -> InsertQuery p -> IO (PreparedInsertQuery p)
Same as prepare
.
runInsertQuery :: (IConnection conn, ToSql SqlValue p) => conn -> InsertQuery p -> p -> IO Integer
Prepare insert statement, bind parameters, execute statement and get execution result.
Update
Actions to manage UPDATE statements.
prepareUpdate :: IConnection conn => conn -> Update p -> IO (PreparedUpdate p)
Same as prepare
.
runUpdate :: (IConnection conn, ToSql SqlValue p) => conn -> Update p -> p -> IO Integer
Prepare update statement, bind parameters, execute statement and get execution result.
Delete
Actions to manage DELETE statements.
prepareDelete :: IConnection conn => conn -> Delete p -> IO (PreparedDelete p)
Same as prepare
.
runDelete :: (IConnection conn, ToSql SqlValue p) => conn -> Delete p -> p -> IO Integer
Prepare delete statement, bind parameters, execute statement and get execution result.
Update by Key
Actions to manage UPDATE statements which updates columns other than specified key of the records selected by specified key.
prepareKeyUpdate :: IConnection conn => conn -> KeyUpdate p a -> IO (PreparedKeyUpdate p a)
Same as prepare
.
bindKeyUpdate :: ToSql SqlValue a => PreparedKeyUpdate p a -> a -> BoundStatement ()
Typed operation to bind parameters for PreparedKeyUpdate
type.
runKeyUpdate :: (IConnection conn, ToSql SqlValue a) => conn -> KeyUpdate p a -> a -> IO Integer
Prepare insert statement, bind parameters, execute statement and get execution result.