Expressions are constructed by using operands and operators.
An Example of a Simple PL/SQL Expression
SQL>
SQL> declare
2 v_i1 NUMBER;
3 v_i2 NUMBER;
4 begin
5 v_i1:=10/3;
6 v_i2:=-v_i1;
7 end;
8 /
PL/SQL procedure successfully completed.
SQL>