Supplying Parameters Through Host or Program Variables
You pass parameters to the database server by opening the cursor with the USING keyword, followed by the names of the variables. These variables are matched with prepared statement question-mark ( ? ) placeholders in a one-to-one correspondence, from left to right. You must supply one storage- parameter variable for each placeholder. The data type of each variable must be compatible with the corresponding value that the prepared statement requires.
The following example executes the prepared UPDATE statement in Informix®
ESQL/C:
stcopy ("update orders set order_date = ?
where po_num = ?", stm1);
EXEC SQL prepare statement_1 from :stm1;
EXEC SQL execute statement_1 using :order_date, :po_num;