$dayOfWeek / $dayOfYear / $isoWeek / $isoWeekYear
Reference group: Date expressions
What it does
Extracts weekday, day-of-year, or ISO week data.
Syntax
Date-part expressions
Use case
Weekly reports.
Important notes
ISO week-year may differ from calendar year near New Year.
$dayOfWeek / $dayOfYear / $isoWeek / $isoWeekYear: practical example
{ $project: { week: { $isoWeek: "$createdAt" }, isoYear: { $isoWeekYear: "$createdAt" } } }💡 Explanation
Extracts weekday, day-of-year, or ISO week data.
When to use it
Weekly reports.
Caution
ISO week-year may differ from calendar year near New Year.
Key Takeaways
- Extracts weekday, day-of-year, or ISO week data.
- Typical use: Weekly reports.