| For This Calendar... | The First Full Week Begins... |
|---|---|
| Teradata | on Sunday. The days of the year before Sunday belong to Week 0. For example, if the year starts on January 1, 2004 (a Thursday), then Week 0 is from January 1 to January 3. Week 1 begins on Sunday, January 4. |
| ISO | on Monday. The first week of the year is the first week that has at least 4 days. If a week has fewer than 4 days, it belongs to the last week of the previous year. There are no partial weeks. This calendar follows the ISO and European standard. For example, if the year starts on January 1, 2008 (a Tuesday) and the week start is Monday, week 1 of 2008 is from December 31, 2007, to January 6, 2008. |
| COMPATIBLE | on January 1. regardless of what day of the week that is. There can be partial weeks with 1 day (for most years) or 2 days (for leap years) at the end of the year. The day the week begins can change from year to year. This calendar is Oracle-compatible. For example, if January 1, 2011, is a Saturday, the first week of the year is from Saturday, January 1, 2011, through Friday, January 7, 2011. |