#Oracle week number starting sunday mod
#Oracle week number starting sunday full
#Oracle week number starting sunday iso

if you look at the formula bar starting with Table.Transform you will noice there Date.WeekOfYear function being used. Most years have 52 weeks, but if the year starts on a Thursday or is a leap year that starts on a Wednesday, that particular year will have 53 numbered weeks. results in, because it is the start of the week June 6th is in). Read more about TO_CHAR() in the Oracle manual. To get the corresponding four-digit year, use SELECT TO_CHAR(datecol, 'IYYY') FROM ….

#Oracle week number starting sunday iso

To get the ISO week number (1-53) from a date in the column datecol, use SELECT TO_CHAR(datecol, 'IW') FROM ….

#Oracle week number starting sunday full

In essence, the calculation happens in three steps calculate the number of full (not partial) weeks between the two dates, multiply that by five, add the number of weekdays in the starting week, and finally add the number of weekdays in the finishing week. The ISO week method to find the first Friday on or after the input is trickier. Syntax: WEEK(date) iw seems to be the ISO standard for weeks. If January 1 falls on a Friday, Saturday, or Sunday, then the week including January 1 is the last week of the previous year, because most of the days in the week belong to the previous year. Let’s say, we are loading dates for the week of.

Each week's year is the Gregorian year in which the Thursday falls.

#Oracle week number starting sunday mod

The formula for this is: Copy code snippet date + 6 - mod ( ( date + 6 - day of week number ) - start of ISO week, 7 ) The day numbers are 0-6, with zero being Monday and six Sunday. The first week is equivalent to the following two variants: the week that contains the first Thursday of the Gregorian year and the week containing January 4th.

By moving the anchor date slightly, you can hardcode any day as the first day of a week.Ĭorrection to your example: if today is 02/mar/2018 then start date is 24/feb/2018 but end date is 02/mar/2018, not 03/mar/2018.For example, January of 2005 should be in the report for having six weeks, Jan 1 is Saturday, this is week 1, Week 2 is from 2 to 8, and the last week, week 6 has 30 and 31. The end date is obviously the start date plus 6 days. This offset is subtracted from today, giving the closest Saturday before today. (You could use any Saturday before your oldest 'today' as the anchor.) The modulo (MOD) expression returns 0 if today is Saturday, 1 if it is Sunday, etc. The above query uses the Julian date (2415026) of the first Saturday in the 20th century (January 6th, 1900) as an anchor point. If you want to hardcode the week start to Saturday and make it independent of NLS settings, then you need to do some more complex date arithmetic, because TRUNC does not accept NLS_TERRITORY as a direct parameter: It will start on Saturday in Arabic countries. The above query adapts to the week definition for a given territory: the week will start on Sunday in US and on Monday in Europe. If you can control the NLS territory setting (or even better: you want to adapt to it), then the simplest solution is to use TRUNC(SYSDATE,'D') and TRUNC(SYSDATE,'D')+6 :Īlter session set nls_territory='saudi arabia' įrom (select date ''+level today from dual connect by level<=10)