In MongoDB, the $isoWeek aggregation pipeline operator returns the week number in ISO 8601 format, ranging from 1 to 53.
When using the $isoWeek operator, you can optionally specify a timezone to use for the result.
The $isoWeek operator accepts either a date (as either a Date, a Timestamp, or an ObjectId), or a document that specifies the date and timezone to use.
In MongoDB, the $isoDayOfWeek aggregation pipeline operator returns the weekday number in ISO 8601 format, ranging from 1 (for Monday) to 7 (for Sunday).
You can optionally specify a timezone to use for the result.
The $isoDayOfWeek operator accepts either a date (as either a Date, a Timestamp, or an ObjectId), or a document that specifies the date and timezone to use.
In MongoDB, the $dayOfWeek aggregation pipeline operator returns the day of the week for a date as a number between 1 (Sunday) and 7 (Saturday).
You can optionally specify a timezone to use for the result.
The $dayOfWeek operator accepts either a date (as either a Date, a Timestamp, or an ObjectId), or a document that specifies the date and timezone to use.
In MongoDB, the $dayOfMonth aggregation pipeline operator returns the day of the month for a date as a number between 1 and 31.
You can optionally specify a timezone to use for the result.
The $dayOfMonth operator accepts either a date (as either a Date, a Timestamp, or an ObjectId), or a document that specifies the date and timezone to use.
In MongoDB, the $dayOfYear aggregation pipeline operator returns the day of the year for a date as a number between 1 and 366.
You can optionally specify a timezone to use for the result.
The $dayOfYear operator accepts either a date (as either a Date, a Timestamp, or an ObjectId), or a document that specifies the date and timezone to use.
I thought it would be interesting to run a few quick queries to see how various formatting strings affect the formatting of date/time values.
In PostgreSQL, you can use the to_char() function to return dates in various formats.
One of the things you can do with this function is return the month portion of a date in roman numerals.
Continue readingIn PostgreSQL you can use the extract() function to get the week number from a date.
You can also use the date_part() function to do the same thing.
In PostgreSQL, you can use the to_char() function to get the short day name from a date.
By “short day name” I mean the abbreviated day name, for example Fri, Mon, etc.
The to_char() function accepts two parameters; the date and the format string with which to format that date.
In PostgreSQL you can use the extract() function to get the day from a date.
You can also use date_part() to do the same thing.
When extracting the day from a date, you need to specify what sense of the word “day” you mean. For example, “day of week”, “day of month”, “day of year”, etc.