A. This statement is incorrect because TO_NUMBER expects a character string as an argument, not a date. Directly converting a date to a number without an intermediate conversion to a character string would result in an error. B. This statement is incorrect. Multiplying a date by a number does not make sense in SQL, and attempting to convert such an expression to a date will also result in an error. C. This statement is correct. Subtracting two dates in Oracle SQL results in the number of days between those dates, hence the result is a number. D. This statement is correct. Subtracting a number from a date in Oracle SQL will subtract that number of days from the date, returning another date. E. This statement is incorrect. As stated in C, subtracting a date from SYSDATE correctly returns the number of days between those two dates, not an error.
These concepts are explained in the Oracle Database SQL Language Reference, which details date arithmetic in SQL.
Contribute your Thoughts:
Chosen Answer:
This is a voting comment (?). You can switch to a simple comment. It is better to Upvote an existing comment if you don't have anything to add.
Submit