Modulepersistent-2.18.1.0Haskell2010

Database.Persist.FieldDef.Internal

Synopsis

data FieldDef
value isFieldNotGenerated
data FieldCascade
value renderFieldCascade
value renderCascadeAction
value noCascade
data CascadeAction

Packagepersistent-2.18.1.0
Exports7
LanguageHaskell2010
LicenceMIT
SourceInternal.hs

datadata FieldDef

A FieldDef represents the inormation that persistent knows about a field of a datatype. This includes information used to parse the field out of the database and what the field corresponds to.

Constructors

FieldDef
- fieldHaskell :: !FieldNameHS
  The name of the field. Note that this does not corresponds to the record labels generated for the particular entity - record labels are generated with the type name prefixed to the field, so a FieldDef that contains a FieldNameHS "name" for a type User will have a record field userName.
- fieldDB :: !FieldNameDB
  The name of the field in the database. For SQL databases, this corresponds to the column name.
- fieldType :: !FieldType
  The type of the field in Haskell.
- fieldSqlType :: !SqlType
  The type of the field in a SQL database.
- fieldAttrs :: ![FieldAttr]
  User annotations for a field. These are provided with the ! operator.
- fieldStrict :: !Bool
  If this is True, then the Haskell datatype will have a strict record field. The default value for this is True.
- fieldReference :: !ReferenceDef
- fieldCascade :: !FieldCascade
  Defines how operations on the field cascade on to the referenced tables. This doesn't have any meaning if the fieldReference is set to NoReference or SelfReference. The cascade option here should be the same as the one obtained in the fieldReference.
- fieldComments :: !Maybe Text
  Optional comments for a Field.
- fieldGenerated :: !Maybe Text
  Whether or not the field is a GENERATED column, and additionally the expression to use for generation.
- fieldIsImplicitIdColumn :: !Bool
  True if the field is an implicit ID column. False otherwise.

Instances5Eq, Ord, Read, Show, Lift

Eq FieldDefDefined in persistent-2.18.1.0 · Database.Persist.Types.Base
Ord FieldDefDefined in persistent-2.18.1.0 · Database.Persist.Types.Base
Read FieldDefDefined in persistent-2.18.1.0 · Database.Persist.Types.Base
Show FieldDefDefined in persistent-2.18.1.0 · Database.Persist.Types.Base
Lift FieldDefDefined in persistent-2.18.1.0 · Database.Persist.Types.Base

valueisFieldNotGenerated :: FieldDef -> Bool

datadata FieldCascade

Source#

This datatype describes how a foreign reference field cascades deletes or updates.

This type is used in both parsing the model definitions and performing migrations. A Nothing in either of the field values means that the user has not specified a CascadeAction. An unspecified CascadeAction is defaulted to Restrict when doing migrations.

Constructors

FieldCascade
- fcOnUpdate :: !Maybe CascadeAction
- fcOnDelete :: !Maybe CascadeAction

Instances5Eq, Ord, Read, Show, Lift

Eq FieldCascadeDefined in persistent-2.18.1.0 · Database.Persist.Types.Base
Ord FieldCascadeDefined in persistent-2.18.1.0 · Database.Persist.Types.Base
Read FieldCascadeDefined in persistent-2.18.1.0 · Database.Persist.Types.Base
Show FieldCascadeDefined in persistent-2.18.1.0 · Database.Persist.Types.Base
Lift FieldCascadeDefined in persistent-2.18.1.0 · Database.Persist.Types.Base

valuerenderFieldCascade :: FieldCascade -> Text

Source#

Renders a FieldCascade value such that it can be used in SQL migrations.

valuerenderCascadeAction :: CascadeAction -> Text

Source#

Render a CascadeAction to Text such that it can be used in a SQL command.

valuenoCascade :: FieldCascade

Source#

A FieldCascade that does nothing.

datadata CascadeAction

Source#

An action that might happen on a deletion or update on a foreign key change.

Cascade Restrict SetNull SetDefault NoAction

Instances5Eq, Ord, Read, Show, Lift

Eq CascadeActionDefined in persistent-2.18.1.0 · Database.Persist.Types.Base
Ord CascadeActionDefined in persistent-2.18.1.0 · Database.Persist.Types.Base
Read CascadeActionDefined in persistent-2.18.1.0 · Database.Persist.Types.Base
Show CascadeActionDefined in persistent-2.18.1.0 · Database.Persist.Types.Base
Lift CascadeActionDefined in persistent-2.18.1.0 · Database.Persist.Types.Base