Use a named row type to create a typed table

You can create a table that is typed or untyped. A typed table is a table that has a named row type assigned to it. An untyped table is a table that does not have a named row type assigned to it. The CREATE ROW TYPE statement creates a named row type but does not allocate storage for instances of the row type. To allocate storage for instances of a named row type, you must assign the row type to a table. The following example shows how to create a typed table:
CREATE ROW TYPE person_t
(
   name     VARCHAR(30),
   address  VARCHAR(20),
   city     VARCHAR(20),
   state    CHAR(2),
   zip      INTEGER,
   bdate    DATE
);

CREATE TABLE person OF TYPE person_t;
The first statement creates the person_t type. The second statement creates the person table, which contains instances of the person_t type. More specifically, each row in a typed table contains an instance of the named row type that is assigned to the table. In the preceding example, the fields of the person_t type define the columns of the person table.
Important: The order in which you create named row types is important because a named row type must exist before you can use it to define a typed table.
Inserting data into a typed table is no different than inserting data into an untyped table. When you insert data into a typed table, the operation creates an instance of the row type and inserts it into the table. The following example shows how to insert a row into the person table:
INSERT INTO person 
VALUES ('Brown, James', '13 First St.', 'San Carlos', 'CA', 94070,
'01/04/1940')

The INSERT statement creates an instance of the person_t type and inserts it into the table. For more information about how to insert, update, and delete columns that are defined on named row types, see the IBM® Informix® Guide to SQL: Tutorial.

You can use a single named row type to create multiple typed tables. In this case, each table has a unique name, but all tables share the same type.
Restriction: You cannot create a typed table that is a temporary table.

For information about the advantages of using typed tables when you implement your data model, see Type inheritance.