Calling a Function in a Database

A function is essentially a stored procedure that returns a result. This example demonstrates how to call functions with IN, OUT, and IN/OUT parameters.

CallableStatement cs; try {
// Call a function with no parameters;
the function returns a VARCHAR // Prepare the CallableStatement
cs = connection.prepareCall("{? = call myfunc}"); // Register the type of the return value
cs.registerOutParameter(1, i); // Execute and retrieve the returned value cs.execute(); String retValue = cs.getString(1); // Call a function with one IN parameter; the function returns a VARCHAR
cs = connection.prepareCall("{? = call myfuncin(?)}"); // Register the type of the return value
cs.registerOutParameter(1, Types.VARCHAR); // Set the value for the IN parameter cs.setString(2, "a string"); // Execute and retrieve the returned value cs.execute(); retValue = cs.getString(1); // Call a function with one OUT parameter; the function returns a VARCHAR
cs = connection.prepareCall("{? = call myfuncout(?)}"); // Register the types of the return value and OUT parameter
cs.registerOutParameter(1, Types.VARCHAR); cs.registerOutParameter(2, Types.VARCHAR); // Execute and retrieve the returned values cs.execute();
retValue = cs.getString(1); // return value String outParam = cs.getString(2); // OUT parameter // Call a function with one IN/OUT parameter; the function returns a VARCHAR cs = connection.prepareCall("{? = call myfuncinout(?)}"); // Register the types of the return value and OUT parameter
cs.registerOutParameter(1, Types.VARCHAR); cs.registerOutParameter(2, Types.VARCHAR); // Set the value for the IN/OUT parameter
cs.setString(2, "a string"); // Execute and retrieve the returned values cs.execute(); retValue = cs.getString(1); // return value outParam = cs.getString(2); // IN/OUT parameter } catch (SQLException e) { }