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1. getPsIdName :: PersistSettings -> Text

   persistent	Database.Persist.Quasi.PersistSettings.Internal

   Retrieve the default name of the id column.

2. psIdName :: PersistSettings -> !Text

   persistent	Database.Persist.Quasi.PersistSettings.Internal

   The name of the id column. Default value: id The name of the id column can also be changed on a per-model basis https://github.com/yesodweb/persistent/wiki/Persistent-entity-syntax

3. setPsIdName :: Text -> PersistSettings -> PersistSettings

   persistent	Database.Persist.Quasi.PersistSettings.Internal

   Set the default name of the id column.

4. data BackendSpecificOverrides

   persistent	Database.Persist.Sql

   Record of functions to override the default behavior in mkColumns. It is recommended you initialize this with emptyBackendSpecificOverrides and override the default values, so that as new fields are added, your code still compiles. For added safety, use the getBackendSpecific* and setBackendSpecific* functions, as a breaking change to the record field labels won't be reflected in a major version bump of the library.

5. connectionPoolConfigIdleTimeout :: ConnectionPoolConfig -> NominalDiffTime

   persistent	Database.Persist.Sql

   How long connections can remain idle before being disposed of, in seconds. Default: 600

6. emptyBackendSpecificOverrides :: BackendSpecificOverrides

   persistent	Database.Persist.Sql

   Creates an empty BackendSpecificOverrides (i.e. use the default behavior; no overrides)

7. dbIdColumns :: SqlBackend -> EntityDef -> NonEmpty Text

   persistent	Database.Persist.Sql.Util

   No documentation available.

8. dbIdColumnsEsc :: (FieldNameDB -> Text) -> EntityDef -> NonEmpty Text

   persistent	Database.Persist.Sql.Util

   No documentation available.

9. isIdField :: PersistEntity record => EntityField record typ -> Bool

   persistent	Database.Persist.Sql.Util

   No documentation available.

10. data ImplicitIdDef

    persistent	Database.Persist.TH

    A specification for how the implied ID columns are created. By default, persistent will give each table a default column named id (customizable by PersistSettings), and the column type will be whatever you'd expect from BackendKey yourBackendType. For The SqlBackend type, this is an auto incrementing integer primary key. You might want to give a different example. A common use case in postgresql is to use the UUID type, and automatically generate them using a SQL function. Previously, you'd need to add a custom Id annotation for each model.

    User
    Id   UUID default="uuid_generate_v1mc()"
    name Text
    
    Dog
    Id   UUID default="uuid_generate_v1mc()"
    name Text
    user UserId
    

    Now, you can simply create an ImplicitIdDef that corresponds to this declaration.

    newtype UUID = UUID ByteString
    
    instance PersistField UUID where
    toPersistValue (UUID bs) =
    PersistLiteral_ Escaped bs
    fromPersistValue pv =
    case pv of
    PersistLiteral_ Escaped bs ->
    Right (UUID bs)
    _ ->
    Left "nope"
    
    instance PersistFieldSql UUID where
    sqlType _ = SqlOther UUID
    

    With this instance at the ready, we can now create our implicit definition:

    uuidDef :: ImplicitIdDef
    uuidDef = mkImplicitIdDef @UUID "uuid_generate_v1mc()"
    

    And we can use setImplicitIdDef to use this with the MkPersistSettings for our block.

    mkPersist (setImplicitIdDef uuidDef sqlSettings) [persistLowerCase| ... |]
    

    TODO: either explain interaction with mkMigrate or fix it. see issue #1249 for more details.

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