e296. creating an object type in an oracle database.txt

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In Oracle, you can define a composite data structure called an OBJECT, which consists of one or more basic types. For example, you could define an object called book with a title (VARCHAR) and an price (NUMBER). An OBJECT can also contain other OBJECTs. 
This example creates two OBJECT types. object2 contains two fields --- a string and a number while object1 also contains two fields --- a string and a value of type object2. 

The example also creates a table to hold object1 values. See also e297 Inserting an OBJECT Value into an Oracle Table. 

    try {
        // Create a statement
        Statement stmt = connection.createStatement();
    
        // Create the object2 type
        stmt.execute("CREATE TYPE object2 AS OBJECT"
            + "(col_string2 VARCHAR(30), col_integer2 NUMBER)");
    
        // Create the object1 type
        stmt.execute("CREATE TYPE object1 AS OBJECT"
            + "(col_string1 VARCHAR(30), col_integer2 object2)");
    
        // Create a table with a column to hold a number and the new object1 type
        stmt.execute("CREATE TABLE object1_table(col_integer NUMBER, col_object1 object1)");
    } catch (SQLException e) {
    }