If the parameter value entered in the function can be converted to the specified type, the parameter type will be converted. The strings are converted to numbers because the input parameter expected in the following function is a number.
SELECT MOD('123','2');
mod('123', '2')
==========================
1.000000000000000e+00
You can enter multiple type values in the function. If the type value not specified in the function is delivered, the type will be converted depending on the following priority order.