Preparing the SQL Statement

The STRING created in the query-by-example is not valid for execution. The PREPARE instruction sends the text of the string to the database server for parsing, validation, and to generate the execution plan.

The scope of a prepared SQL statement is the module in which it is declared.
PREPARE cust_cnt_stmt FROM sql_text
A prepared SQL statement can be executed with the EXECUTE instruction.
EXECUTE cust_cnt_stmt INTO cust_cnt

Since the SQL statement will only return one row (containing the count) the INTO syntax of the EXECUTE instruction can be used to store the count in the local variable cust_cnt. (The function cust_select illustrates the use of database cursors with SQL SELECT statements.)

When a prepared statement is no longer needed, the FREE instruction will release the resources associated with the statement.
FREE cust_cnt_stmt