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1. SideData :: DistinctClause -> [FromClause] -> [SetClause] -> WhereClause -> GroupByClause -> HavingClause -> [OrderByClause] -> LimitClause -> LockingClause -> [CommonTableExpressionClause] -> SideData

   esqueleto	Database.Esqueleto.Internal.Internal

   No documentation available.

2. class ToBaseId ent

   esqueleto	Database.Esqueleto.Internal.Internal

   Class that enables one to use toBaseId to convert an entity's key on a query into another (cf. toBaseId).

3. aliasedEntityColumnIdent :: Ident -> FieldDef -> Ident

   esqueleto	Database.Esqueleto.Internal.Internal

   No documentation available.

4. collectIdents :: FromClause -> Set Ident

   esqueleto	Database.Esqueleto.Internal.Internal

   No documentation available.

5. fromBaseId :: ToBaseId ent => SqlExpr (Value (Key (BaseEnt ent))) -> SqlExpr (Value (Key ent))

   esqueleto	Database.Esqueleto.Internal.Internal

   The inverse of toBaseId. Note that this is somewhat less "safe" than toBaseId. Calling toBaseId will usually mean that a foreign key constraint is present that guarantees the presence of the base ID. fromBaseId has no such guarantee. Consider the code example given in toBaseId:

   Bar
   barNum Int
   Foo
   bar BarId
   fooNum Int
   Primary bar
   

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

   The type of toBaseId for Foo would be:

   toBaseId :: SqlExpr (Value FooId) -> SqlExpr (Value BarId)
   

   The foreign key constraint on Foo means that every FooId points to a BarId in the database. However, fromBaseId will not have this:

   fromBaseId :: SqlExpr (Value BarId) -> SqlExpr (Value FooId)
   

6. fromBaseIdMaybe :: ToBaseId ent => SqlExpr (Value (Maybe (Key (BaseEnt ent)))) -> SqlExpr (Value (Maybe (Key ent)))

   esqueleto	Database.Esqueleto.Internal.Internal

   As fromBaseId, but works on Maybe keys.

7. initialIdentState :: IdentState

   esqueleto	Database.Esqueleto.Internal.Internal

   No documentation available.

8. newIdentFor :: DBName -> SqlQuery Ident

   esqueleto	Database.Esqueleto.Internal.Internal

   Create a fresh Ident. If possible, use the given DBName.

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

   esqueleto	Database.Esqueleto.Internal.Internal

   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.

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

    esqueleto	Database.Esqueleto.Internal.Internal

    Like toBaseId, but works on Maybe keys.

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