Language Integrated Query (LINQ) defines a set of operators that can be used to query, project, and filter data in arrays, enumerable classes, XML, relational databases, and other data sources. One form of LINQ, LINQ to Entities, allows querying of Entity Framework data sources. ODP.NET supports Entity Framework such that the Oracle database can participate in object-relational modeling and LINQ to Entities queries.
Entity SQL is a language that enables querying of Entity Framework conceptual models. It allows querying Entity Framework entities and relationships in a format that is similar to SQL. ODP.NET supports querying Oracle databases through Entity SQL.
LINQ and Entity SQL syntax are generally data source neutral.