These examples all create a 3-dimensional ARRAY type named seismic_cube based on the UDT measures_udt, which has the following SQL create text.
CREATE TYPE measures_udt AS ( amplitude INTEGER, phase INTEGER, frequency INTEGER);
The first example uses Teradata-style syntax and initializes all of its elements to nulls.
CREATE TYPE seismic_cube AS measures_udt ARRAY [1:5][1:7][1:20] DEFAULT NULL;
The next example also uses Teradata-style syntax, but does not initialize its elements to nulls.
CREATE TYPE seismic_cube AS measures_udt ARRAY [1:5][1:7][1:20];