uint64_t mysql_stmt_affected_rows(MYSQL_STMT *stmt)
be called immediately after executing a statement with
mysql_stmt_execute(). It is
for prepared statements. For a description of what the
affected-rows value returned by this function means, See
Section 5.4.1, “mysql_affected_rows()”.
See the Example in Section 6.4.10, “mysql_stmt_execute()”.