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1. persistUniqueKeys :: PersistEntity record => record -> [Unique record]

   persistent	Database.Persist.Class.PersistEntity

   A meta operation to retrieve all the Unique keys.

2. persistUniqueToFieldNames :: PersistEntity record => Unique record -> NonEmpty (FieldNameHS, FieldNameDB)

   persistent	Database.Persist.Class.PersistEntity

   A lower level operation.

3. persistUniqueToValues :: PersistEntity record => Unique record -> [PersistValue]

   persistent	Database.Persist.Class.PersistEntity

   A lower level operation.

4. persistBackend :: HasPersistBackend backend => backend -> BaseBackend backend

   persistent	Database.Persist.Class.PersistStore

   No documentation available.

5. persistUniqueKeyValues :: PersistEntity record => record -> [PersistValue]

   persistent	Database.Persist.Class.PersistUnique

   This function returns a list of PersistValue that correspond to the Unique keys on that record. This is useful for comparing two records for equality only on the basis of their Unique keys.

6. persistBackend :: HasPersistBackend backend => backend -> BaseBackend backend

   persistent	Database.Persist.Sql.Types.Internal

   No documentation available.

7. persistFieldFromEntity :: MkPersistSettings -> UnboundEntityDef -> Q [Dec]

   persistent	Database.Persist.TH

   Produce code similar to the following:

   instance PersistEntity e => PersistField e where
   toPersistValue = entityToPersistValueHelper
   fromPersistValue = entityFromPersistValueHelper ["col1", "col2"]
   sqlType _ = SqlString
   

8. persistFileWith :: PersistSettings -> FilePath -> Q Exp

   persistent	Database.Persist.TH

   Same as persistWith, but uses an external file instead of a quasiquotation. The recommended file extension is .persistentmodels.

9. persistLowerCase :: QuasiQuoter

   persistent	Database.Persist.TH

   Apply persistWith to lowerCaseSettings.

10. persistManyFileWith :: PersistSettings -> [FilePath] -> Q Exp

    persistent	Database.Persist.TH

    Same as persistFileWith, but uses several external files instead of one. Splitting your Persistent definitions into multiple modules can potentially dramatically speed up compile times. The recommended file extension is .persistentmodels.

    Examples

    Split your Persistent definitions into multiple files (models1, models2), then create a new module for each new file and run mkPersist there:

    -- Model1.hs
    share
    [mkPersist sqlSettings]
    $(persistFileWith lowerCaseSettings "models1")
    

    -- Model2.hs
    share
    [mkPersist sqlSettings]
    $(persistFileWith lowerCaseSettings "models2")
    

    Use persistManyFileWith to create your migrations:

    -- Migrate.hs
    mkMigrate "migrateAll"
    $(persistManyFileWith lowerCaseSettings ["models1.persistentmodels","models2.persistentmodels"])
    

    Tip: To get the same import behavior as if you were declaring all your models in one file, import your new files as Name into another file, then export module Name. This approach may be used in the future to reduce memory usage during compilation, but so far we've only seen mild reductions. See persistent#778 and persistent#791 for more details.

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