how to get the 1st day of the year sql query oracle

I need a sql query to get a 1st day of the 1st month of the year which i am passing.

ex: If i am passing 2021, my output should be 01-JAN-2021 If i am passing 2020, my output should be 01-JAN-2020

Answer

Assuming you are passing the year as the bind variable :year then:

SELECT TO_DATE(:year||'0101','YYYYMMDD')
FROM   DUAL;

or

SELECT TRUNC(TO_DATE(:year,'YYYY'),'YY')
FROM   DUAL;