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1. toBaseId :: ToBaseId ent => SqlExpr (Value (Key ent)) -> SqlExpr (Value (Key (BaseEnt ent)))

   esqueleto	Database.Esqueleto

   Convert an entity's key into another entity's. This function is to be used when you change an entity's Id to be that of another entity. For example:

   Bar
   barNum Int
   Foo
   bar BarId
   fooNum Int
   Primary bar
   

   In this example, Bar is said to be the BaseEnt(ity), and Foo the child. To model this in Esqueleto, declare:

   instance ToBaseId Foo where
   type BaseEnt Foo = Bar
   toBaseIdWitness barId = FooKey barId
   

   Now you're able to write queries such as:

   select $
   from $ (bar `InnerJoin` foo) -> do
   on (toBaseId (foo ^. FooId) ==. bar ^. BarId)
   return (bar, foo)
   

   Note: this function may be unsafe to use in conditions not like the one of the example above.

2. toBaseIdMaybe :: ToBaseId ent => SqlExpr (Value (Maybe (Key ent))) -> SqlExpr (Value (Maybe (Key (BaseEnt ent))))

   esqueleto	Database.Esqueleto

   Like toBaseId, but works on Maybe keys.

3. toBaseIdWitness :: ToBaseId ent => Key (BaseEnt ent) -> Key ent

   esqueleto	Database.Esqueleto

   Convert from the key of the BaseEnt(ity) to the key of the child entity. This function is not actually called, but that it typechecks proves this operation is safe.

4. data BackendSpecificOverrides

   esqueleto	Database.Esqueleto.Experimental

   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. Divide :: PersistUpdate

   esqueleto	Database.Esqueleto.Experimental

   No documentation available.

6. data EntityIdDef

   esqueleto	Database.Esqueleto.Experimental

   The definition for the entity's primary key ID.

7. EntityIdField :: FieldDef -> EntityIdDef

   esqueleto	Database.Esqueleto.Experimental

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

8. EntityIdNaturalKey :: CompositeDef -> EntityIdDef

   esqueleto	Database.Esqueleto.Experimental

   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.

9. PersistInvalidField :: Text -> PersistException

   esqueleto	Database.Esqueleto.Experimental

   No documentation available.

10. PersistObjectId :: ByteString -> PersistValue

    esqueleto	Database.Esqueleto.Experimental

    Intended especially for MongoDB backend

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