The value of a variable is an array of zero or more values. A
reference to a variable will normally print its 0th (first) value, if
any. Inside a
SQL statement, however, only the
current value is used. This simplifies iterating a list of
values, such as when creating checkboxes for a form (see
here for details).
Variables can be assigned values in many ways, such as with an
assignment statement (here); as the result rows
<SQL> statement (here); or as the return value
of builtin/user functions (e.g.