Standard sql syntax is compatible, such as the syntax of subquery, and the difference is only the way of using functions.
Isnull and nvl
Row_number() over and rownumber ()
Ceiling and ceiling
Log and ln
Power of sum of squares
+and ||
Substring and substring
Lens and length
Get date and system date
The above and so on are all functions with the same function.
Of course, there are also cases where the parameter order of the same name function is different, so I won't list them one by one.