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1. getByValue :: forall record (m :: Type -> Type) backend . (MonadIO m, PersistUniqueRead backend, PersistRecordBackend record backend, AtLeastOneUniqueKey record) => record -> ReaderT backend m (Maybe (Entity record))

   esqueleto	Database.Esqueleto.Experimental

   A modification of getBy, which takes the PersistEntity itself instead of a Unique record. Returns a record matching one of the unique keys. This function makes the most sense on entities with a single Unique constructor.

   Example usage

   With schema-1 and dataset-1, getBySpjValue :: MonadIO m => ReaderT SqlBackend m (Maybe (Entity User)) getBySpjValue = getByValue $ User SPJ 999

   mSpjEnt <- getBySpjValue
   

   The above query when applied on dataset-1, will get this record:

   +----+------+-----+
   | id | name | age |
   +----+------+-----+
   |  1 | SPJ  |  40 |
   +----+------+-----+
   

2. keyFromValues :: PersistEntity record => [PersistValue] -> Either Text (Key record)

   esqueleto	Database.Esqueleto.Experimental

   A lower-level key operation.

3. keyToValues :: PersistEntity record => Key record -> [PersistValue]

   esqueleto	Database.Esqueleto.Experimental

   A lower-level key operation.

4. keyValueEntityFromJSON :: (PersistEntity record, FromJSON record) => Value -> Parser (Entity record)

   esqueleto	Database.Esqueleto.Experimental

   Predefined parseJSON. The input JSON looks like {"key": 1, "value": {"name": ...}}. The typical usage is:

   instance FromJSON (Entity User) where
   parseJSON = keyValueEntityFromJSON
   

5. keyValueEntityToJSON :: (PersistEntity record, ToJSON record) => Entity record -> Value

   esqueleto	Database.Esqueleto.Experimental

   Predefined toJSON. The resulting JSON looks like {"key": 1, "value": {"name": ...}}. The typical usage is:

   instance ToJSON (Entity User) where
   toJSON = keyValueEntityToJSON
   

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

   esqueleto	Database.Esqueleto.Experimental

   A lower level operation.

7. toPersistValue :: PersistField a => a -> PersistValue

   esqueleto	Database.Esqueleto.Experimental

   No documentation available.

8. toPersistValueJSON :: ToJSON a => a -> PersistValue

   esqueleto	Database.Esqueleto.Experimental

   Convenience function for getting a free PersistField instance from a type with JSON instances. Example usage in combination with fromPersistValueJSON:

   instance PersistField MyData where
   fromPersistValue = fromPersistValueJSON
   toPersistValue = toPersistValueJSON
   

9. unValue :: Value a -> a

   esqueleto	Database.Esqueleto.Experimental

   No documentation available.

10. AliasedValueErr :: UnexpectedValueError -> EsqueletoError

    esqueleto	Database.Esqueleto.Internal.Internal

    No documentation available.

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