Sequences in PL/SQL expressions

Prior to Oracle 11g Release1, in order to access sequence values from within PL/SQL, it was necessary to execute a SQL statement (i.e., SELECT sequence.NEXTVAL from dual; ).  In 11g, you can assign the CURRVAL and NEXTVAL pseudocolumns in PL/SQL expression directly.

The CURRVAL and NEXTVAL make the PL/SQL source text easier and clear. They also improve runtime performance.