HiRDB hasn't equivalents for NUMTOYMINTERVAL function. SQLWays leaves it as is and adds message /* SQLWays: Could not convert 'NUMTOYMINTERVAL' */.

Oracle:

select numtoyminterval(99,'year') from t; 

HiRDB:

select numtoyminterval(99,'year') from t;
/* SQLWays: Could not convert 'numtoyminterval' */