Model

Abstract

One may say that the model clause is the most powerful SQL feature, meaning that it can be used to solve numerous tasks that otherwise would not be resolvable using SQL. This can be accomplished not only because the model clause considerably extends possibilities of declarative SQL, but in addition to that it introduces ability of iterative computations in SQL on top of a recordset. On the other hand, the model clause has some issues with scalability and, in general, a class of problems where the model shines is quite limited. In many cases PL/SQL is preferable even though a result can be achieved using a model clause, but first things first.