Using the USING Clause
If you do not know the number of parameters to be supplied at runtime or their data types, you can associate input values from a system-descriptor area or an sqlda structure. Both of these descriptor structures describe the data type and memory location of one or more values to replace question-mark ( ? ) placeholders.
Each time the PUT statement executes, the values that the descriptor structure describes are used to replace question-mark ( ? ) placeholders in the INSERT statement. This process is similar to using a FROM clause with a list of variables, except that your program has full control over the memory location of the data values.