HI Community,Today, I wishing share to everyone that, to get/select ID of a entitie, using OQL, must declare CAST (function converts an expression to a specific data type). For this, the atribute of return entitie, must be same type of specificated in CAST.The syntax is as follows:CAST ( expression AS data_type )My Example: 'SELECT CAST(c.ID AS Long) AS Entitie_IDFROM MyModule.Entitie AS c'To more: OQL CAST | Mendix Documentation