Consider the following one-dimensional ARRAY data type and table.
CREATE TYPE phonenumbers AS VARRAY(20) OF CHAR(10); CREATE TABLE employee_info (eno INTEGER, phonelist phonenumbers);
The table is populated with the following values:
/* The first 2 elements are populated; the rest are uninitialized. */ INSERT INTO employee_info VALUES (1, phonenumbers('1112223333', '6195551234')); /* Empty ARRAY instance */ INSERT INTO employee_info VALUES (2, phonenumbers()); /* Update empty ARRAY instance such that element 3 is set to a value; Then elements 1 and 2 are set to NULL, the rest are uninitialized */ UPDATE employee_info SET phonelist = '8584850000' WHERE id = 2;
The following query returns the highest subscript value with a populated element in the phonelist array.
SELECT eno, phonelist.OLAST() FROM employee_info;
The following is the result of the query.
ENO phonelist.OLAST() --- ----------------- 1 2 2 3
The following is the same query using function-style syntax.
SELECT eno, OLAST(phonelist) FROM employee_info;