Database.PostgreSQL.PQTypes.Model.Trigger

Trigger name must be unique among triggers of same table. Only CONSTRAINT triggers are supported. They can only be run AFTER an event. The associated functions are always created with no arguments and always RETURN TRIGGER.

For details, see https://www.postgresql.org/docs/11/sql-createtrigger.html.

Trigger functions

data TriggerFunction

Function associated with a trigger.

Since: 1.15.0.0

Constructors

TriggerFunction

Fields

• tfName :: RawSQL ()

  The function's name.

• tfSource :: RawSQL ()

  The functions's body source code.

Instances

Eq TriggerFunction

Defined in Database.PostgreSQL.PQTypes.Model.Trigger

Methods

(==) :: TriggerFunction -> TriggerFunction -> Bool

(/=) :: TriggerFunction -> TriggerFunction -> Bool

Show TriggerFunction

Defined in Database.PostgreSQL.PQTypes.Model.Trigger

Methods

showsPrec :: Int -> TriggerFunction -> ShowS

show :: TriggerFunction -> String

showList :: [TriggerFunction] -> ShowS

sqlCreateTriggerFunction :: TriggerFunction -> RawSQL ()

Build an SQL statement for creating a trigger function.

Since we only support CONSTRAINT triggers, the function will always RETURN TRIGGER and will have no parameters.

Since: 1.15.0.0

sqlDropTriggerFunction :: TriggerFunction -> RawSQL ()

Build an SQL statement for dropping a trigger function.

Since: 1.15.0.0

Triggers

data TriggerEvent

Trigger event name.

Since: 1.15.0.0

Constructors

TriggerInsert

The INSERT event.

TriggerUpdate

The UPDATE event.

TriggerUpdateOf [RawSQL ()]

The UPDATE OF column1 [, column2 ...] event.

TriggerDelete

The DELETE event.

Instances

Eq TriggerEvent

Defined in Database.PostgreSQL.PQTypes.Model.Trigger

Methods

(==) :: TriggerEvent -> TriggerEvent -> Bool

(/=) :: TriggerEvent -> TriggerEvent -> Bool

Ord TriggerEvent

Defined in Database.PostgreSQL.PQTypes.Model.Trigger

Methods

compare :: TriggerEvent -> TriggerEvent -> Ordering

(<) :: TriggerEvent -> TriggerEvent -> Bool

(<=) :: TriggerEvent -> TriggerEvent -> Bool

(>) :: TriggerEvent -> TriggerEvent -> Bool

(>=) :: TriggerEvent -> TriggerEvent -> Bool

max :: TriggerEvent -> TriggerEvent -> TriggerEvent

min :: TriggerEvent -> TriggerEvent -> TriggerEvent

Show TriggerEvent

Defined in Database.PostgreSQL.PQTypes.Model.Trigger

Methods

showsPrec :: Int -> TriggerEvent -> ShowS

show :: TriggerEvent -> String

showList :: [TriggerEvent] -> ShowS

data Trigger

Trigger.

Since: 1.15.0.0

Constructors

Trigger

Fields

• triggerTable :: RawSQL ()

  The table that the trigger is associated with.

• triggerName :: RawSQL ()

  The internal name without any prefixes. Trigger name must be unique among triggers of same table. See triggerMakeName.

• triggerEvents :: Set TriggerEvent

  The set of events. Corresponds to the { event [ OR ... ] } in the trigger definition. The order in which they are defined doesn't matter and there can only be one of each.

• triggerDeferrable :: Bool

  Is the trigger DEFERRABLE or NOT DEFERRABLE ?

• triggerInitiallyDeferred :: Bool

  Is the trigger INITIALLY DEFERRED or INITIALLY IMMEDIATE ?

• triggerWhen :: Maybe (RawSQL ())

  The condition that specifies whether the trigger should fire. Corresponds to the WHEN ( condition ) in the trigger definition.

• triggerFunction :: TriggerFunction

  The function to execute when the trigger fires.

Instances

Eq Trigger

Defined in Database.PostgreSQL.PQTypes.Model.Trigger

Methods

(==) :: Trigger -> Trigger -> Bool

(/=) :: Trigger -> Trigger -> Bool

Show Trigger

Defined in Database.PostgreSQL.PQTypes.Model.Trigger

Methods

showsPrec :: Int -> Trigger -> ShowS

show :: Trigger -> String

showList :: [Trigger] -> ShowS

triggerMakeName :: RawSQL () -> RawSQL () -> RawSQL ()

Make a trigger name that can be used in SQL.

Given a base name and tableName, return a new name that will be used as the actual name of the trigger in an SQL query. The returned name is in the format trg__<tableName>__<name>.

Since: 1.15.0

triggerBaseName :: RawSQL () -> RawSQL () -> RawSQL ()

Return the trigger's base name.

Given the trigger's actual name and tableName, return the base name of the trigger. This is basically the reverse of what triggerMakeName does.

Since: 1.15.0

sqlCreateTrigger :: Trigger -> RawSQL ()

Build an SQL statement that creates a trigger.

Only supports CONSTRAINT triggers which can only run AFTER.

Since: 1.15.0

sqlDropTrigger :: Trigger -> RawSQL ()

Build an SQL statement that drops a trigger.

Since: 1.15.0

createTrigger :: MonadDB m => Trigger -> m ()

Create the trigger in the database.

First, create the trigger's associated function, then create the trigger itself.

Since: 1.15.0

dropTrigger :: MonadDB m => Trigger -> m ()

Drop the trigger from the database.

Since: 1.15.0

getDBTriggers :: forall m. MonadDB m => RawSQL () -> m [Trigger]

Get all noninternal triggers from the database.

Run a query that returns all triggers associated with the given table and marked as tgisinternal = false.

Note that, in the background, to get the trigger's WHEN clause and the source code of the attached function, the entire query that had created the trigger is received using pg_get_triggerdef(t.oid, true)::text and then parsed. The result of that call will be decompiled and normalized, which means that it's likely not what the user had originally typed.

Since: 1.15.0