Database.Persist.EntityDef

An EntityDef represents metadata about a type that persistent uses to store the type in the database, as well as generate Haskell code from it.

Since: 2.13.0.0

The EntityDef type

data EntityDef

An EntityDef represents the information that persistent knows about an Entity. It uses this information to generate the Haskell datatype, the SQL migrations, and other relevant conversions.

Instances

Eq EntityDef

Defined in Database.Persist.Types.Base

Methods

(==) :: EntityDef -> EntityDef -> Bool

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

Ord EntityDef

Defined in Database.Persist.Types.Base

Methods

compare :: EntityDef -> EntityDef -> Ordering

(<) :: EntityDef -> EntityDef -> Bool

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

(>) :: EntityDef -> EntityDef -> Bool

(>=) :: EntityDef -> EntityDef -> Bool

max :: EntityDef -> EntityDef -> EntityDef

min :: EntityDef -> EntityDef -> EntityDef

Read EntityDef

Defined in Database.Persist.Types.Base

Methods

readsPrec :: Int -> ReadS EntityDef

readList :: ReadS [EntityDef]

readPrec :: ReadPrec EntityDef

readListPrec :: ReadPrec [EntityDef]

Show EntityDef

Defined in Database.Persist.Types.Base

Methods

showsPrec :: Int -> EntityDef -> ShowS

show :: EntityDef -> String

showList :: [EntityDef] -> ShowS

Lift EntityDef

Defined in Database.Persist.Types.Base

Methods

lift :: EntityDef -> Q Exp

liftTyped :: EntityDef -> Q (TExp EntityDef)

Construction

Accessors

getEntityHaskellName :: EntityDef -> EntityNameHS

Retrieve the Haskell name of the given entity.

Since: 2.13.0.0

getEntityDBName :: EntityDef -> EntityNameDB

Return the database name for the given entity.

Since: 2.13.0.0

getEntityFields :: EntityDef -> [FieldDef]

Retrieve the list of FieldDef that makes up the fields of the entity.

This does not return the fields for an Id column or an implicit id. It will return the key columns if you used the Primary syntax for defining the primary key.

This does not return fields that are marked SafeToRemove or MigrationOnly - so it only returns fields that are represented in the Haskell type. If you need those fields, use getEntityFieldsDatabase.

Since: 2.13.0.0

getEntityFieldsDatabase :: EntityDef -> [FieldDef]

This returns all of the FieldDef defined for the EntityDef, including those fields that are marked as MigrationOnly (and therefore only present in the database) or SafeToRemove (and a migration will drop the column if it exists in the database).

For all the fields that are present on the Haskell-type, see getEntityFields.

Since: 2.13.0.0

getEntityForeignDefs :: EntityDef -> [ForeignDef]

Since: 2.13.0.0

getEntityUniques :: EntityDef -> [UniqueDef]

Retrieve the list of UniqueDef from an EntityDef. This currently does not include a Primary key, if one is defined. A future version of persistent will include a Primary key among the Unique constructors for the Entity.

Since: 2.13.0.0

getEntityId :: EntityDef -> EntityIdDef

Since: 2.13.0.0

getEntityIdField :: EntityDef -> Maybe FieldDef

Since: 2.13.0.0

getEntityKeyFields :: EntityDef -> NonEmpty FieldDef

Since: 2.13.0.0

getEntityComments :: EntityDef -> Maybe Text

getEntityExtra :: EntityDef -> Map Text [[Text]]

isEntitySum :: EntityDef -> Bool

Since: 2.13.0.0

entityPrimary :: EntityDef -> Maybe CompositeDef

entitiesPrimary :: EntityDef -> NonEmpty FieldDef

Return the [FieldDef] for the entity keys.

keyAndEntityFields :: EntityDef -> NonEmpty FieldDef

Returns a NonEmpty list of FieldDef that correspond with the key columns for an EntityDef.

Setters

setEntityId :: FieldDef -> EntityDef -> EntityDef

Set an entityId to be the given FieldDef.

Since: 2.13.0.0

setEntityIdDef :: EntityIdDef -> EntityDef -> EntityDef

Since: 2.13.0.0

setEntityDBName :: EntityNameDB -> EntityDef -> EntityDef

Since: 2.13.0.0

overEntityFields :: ([FieldDef] -> [FieldDef]) -> EntityDef -> EntityDef

Perform a mapping function over all of the entity fields, as determined by getEntityFieldsDatabase.

Since: 2.13.0.0

Related Types

data EntityIdDef

The definition for the entity's primary key ID.

Since: 2.13.0.0

Constructors

EntityIdField !FieldDef

The entity has a single key column, and it is a surrogate key - that is, you can't go from rec -> Key rec.

Since: 2.13.0.0

EntityIdNaturalKey !CompositeDef

The entity has a natural key. This means you can write rec -> Key rec because all the key fields are present on the datatype.

A natural key can have one or more columns.

Since: 2.13.0.0

Instances

Eq EntityIdDef

Defined in Database.Persist.Types.Base

Methods

(==) :: EntityIdDef -> EntityIdDef -> Bool

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

Ord EntityIdDef

Defined in Database.Persist.Types.Base

Methods

compare :: EntityIdDef -> EntityIdDef -> Ordering

(<) :: EntityIdDef -> EntityIdDef -> Bool

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

(>) :: EntityIdDef -> EntityIdDef -> Bool

(>=) :: EntityIdDef -> EntityIdDef -> Bool

max :: EntityIdDef -> EntityIdDef -> EntityIdDef

min :: EntityIdDef -> EntityIdDef -> EntityIdDef

Read EntityIdDef

Defined in Database.Persist.Types.Base

Methods

readsPrec :: Int -> ReadS EntityIdDef

readList :: ReadS [EntityIdDef]

readPrec :: ReadPrec EntityIdDef

readListPrec :: ReadPrec [EntityIdDef]

Show EntityIdDef

Defined in Database.Persist.Types.Base

Methods

showsPrec :: Int -> EntityIdDef -> ShowS

show :: EntityIdDef -> String

showList :: [EntityIdDef] -> ShowS

Lift EntityIdDef

Defined in Database.Persist.Types.Base

Methods

lift :: EntityIdDef -> Q Exp

liftTyped :: EntityIdDef -> Q (TExp EntityIdDef)