CELKO (1/7/2013)
I would build a calendar table with a ISO-8601 week-within-year format column in addition to the usual Common Era date. This format is 'yyyyWww-d' where yyyy is the year, W is as separator token, ww is (01-53) week number and d is (1-7) day of the week.You input any calendar date, find the week-within-year column and return the dates that match on a LIKE predicate.
WHERE sale_day LIKE '2012W26-[67]'
There are several websites with calendars you can cut & paste, but you can start your search with: http://www.calendar-365.com/week-number.html
Or normalize the components into indexable columns ISOYear, ISOWeek, ISOWeekDay, and avoid the overhead of using LIKE operators.
- Gus "GSquared", RSVP, OODA, MAP, NMVP, FAQ, SAT, SQL, DNA, RNA, UOI, IOU, AM, PM, AD, BC, BCE, USA, UN, CF, ROFL, LOL, ETC
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