Declaring unions and structures

You can declare unions and structures, either directly or by using a type definition (typedef). You can use an element of a union as a host variable, but not the union as a whole. In contrast, a host variable can be either an entire structure or just one of the structure’s elements. The following example declares a union and a structure:

exec sql begin declare section;

     typedef int PAYMENT_METHOD;

     PAYMENT_METHOD method;

     union salary_or_percentage {

         CS_MONEY salary;

         CS_NUMERIC percentage;

         } amount;

      struct employee_record {

         char first_name[30];

         char last_name[30];

         char employee_ID[30];

         } this_employee;

      char *employee_of_the_month_ID = "01234567";

 exec sql end declare section;

 exec sql select first_name, last_name, employee_ID

     into :this_employee

     from employee_table

     where employee_ID = :employee_of_the_month_ID;

 exec sql select payment_type into :method

     from remuneration_table where employee_ID =

     :this_employee.employee_ID;

 switch (method) {

     case SALARIED:

         exec sql select salary into

         :amount.salary

         from remuneration_table

         where employee_ID =

         this_employee.employee_ID;

         break;

     case VOLUNTEER:

         exec sql select 0 into

         :amount.salary

         break;

     case COMMISSION:

         exec sql select commission_percentage into

         :amount.percentage

         from remuneration_table

         where employee_ID =

         this_employee.employee_ID;

         break;

     }