Consider the following structured UDT:
CREATE TYPE measures_UDT AS(amplitude INTEGER, phase INTEGER, frequency INTEGER);
The following statement creates a 3-D ARRAY data type named shots with an element type of measures_UDT.
CREATE TYPE shots AS measures_UDT ARRAY[-2:2][-5:5][-3:3];
The following statement creates a table with a column named shot_ary. The data type of the shot_ary column is shots, which is a 3-D ARRAY type.
CREATE TABLE seismic_table (id INTEGER, shot_ary shots);
The following query selects the value of an element from the 3-D array.
SELECT shot_ary[-1][1][3] FROM seismic_table;