How to Write Multiset Conditions With Oracle VARRAY Types

Oracle is one of the few databases that implements the SQL standard ORDBMS extensions, which essentially allow for nested collections. Other databases that have these features to some extent are CUBRID, Informix, PostgreSQL. Oracle has two types of nested collections: -- Nested tables CREATE TYPE t1 AS TABLE OF VARCHAR2(10); / -- Varrays CREATE TYPE … Continue reading How to Write Multiset Conditions With Oracle VARRAY Types

The power of REF CURSOR types

Many RDBMS have started implementing support for some sort of CURSOR, REF CURSOR or ARRAY/TABLE types. These types have roughly the same semantics as JDBC's  java.sql.Array and java.sql.ResultSet. In principle, such types can appear anywhere in SQL, even if some RDBMS limit support to a certain functionality subset. What exactly are these types? ARRAY types … Continue reading The power of REF CURSOR types