Calculating holidays: number of saturdays and sundays within the given date range query in Oracle

Question

I want to calculate holidays: the number of Saturdays and Sundays within the given date range query in Oracle.

Answer 1

You could use the ROW GENERATOR technique to first generate the dates for a given range, and then count only the SATURDAYs and SUNDAYs.

For example, this query will give me the total count of saturdays and sundays between 1st Jan 2014 and 31st Dec 2014 -

SQL> WITH DATA AS
  2    (SELECT to_date('01/01/2014', 'DD/MM/YYYY') date1,
  3      to_date('31/12/2014', 'DD/MM/YYYY') date2
  4    FROM dual
  5    )
  6  SELECT SUM(holiday) holiday_count
  7  FROM
  8    (SELECT
  9      CASE
 10        WHEN TO_CHAR(date1+LEVEL-1, 'DY','NLS_DATE_LANGUAGE=AMERICAN') IN ('SAT', 'SUN')
 11        THEN 1
 12        ELSE 0
 13      END holiday
 14    FROM data
 15      CONNECT BY LEVEL <= date2-date1+1
 16    )
 17  /

HOLIDAY_COUNT
-------------
          104

SQL>