$dateFromParts
The $dateFromParts operator constructs a date from individual components.
$dateFromParts
The $dateFromParts operator constructs a date from individual components such as year, month, day, hour, minute, second, and millisecond. This operator can be useful when dealing with data that stores date components separately.
Syntax
{
$dateFromParts: {
year: < year > ,
month: < month > ,
day: < day > ,
hour: < hour > ,
minute: < minute > ,
second: < second > ,
millisecond: < millisecond > ,
timezone: < timezone >
}
}Parameters
| Parameter | Description |
|---|---|
year | The year component of the date. |
month | The month component of the date. |
day | The day component of the date. |
hour | The hour component of the date. |
minute | The minute component of the date. |
second | The second component of the date. |
millisecond | The millisecond component of the date. |
timezone | Optional. A timezone specification. |
Examples
Consider this sample document from the stores collection.
{
"_id": "0fcc0bf0-ed18-4ab8-b558-9848e18058f4",
"name": "First Up Consultants | Beverage Shop - Satterfieldmouth",
"location": {
"lat": -89.2384,
"lon": -46.4012
},
"staff": {
"totalStaff": {
"fullTime": 8,
"partTime": 20
}
},
"sales": {
"totalSales": 75670,
"salesByCategory": [
{
"categoryName": "Wine Accessories",
"totalSales": 34440
},
{
"categoryName": "Bitters",
"totalSales": 39496
},
{
"categoryName": "Rum",
"totalSales": 1734
}
]
},
"promotionEvents": [
{
"eventName": "Unbeatable Bargain Bash",
"promotionalDates": {
"startDate": {
"Year": 2024,
"Month": 6,
"Day": 23
},
"endDate": {
"Year": 2024,
"Month": 7,
"Day": 2
}
},
"discounts": [
{
"categoryName": "Whiskey",
"discountPercentage": 7
},
{
"categoryName": "Bitters",
"discountPercentage": 15
},
{
"categoryName": "Brandy",
"discountPercentage": 8
},
{
"categoryName": "Sports Drinks",
"discountPercentage": 22
},
{
"categoryName": "Vodka",
"discountPercentage": 19
}
]
},
{
"eventName": "Steal of a Deal Days",
"promotionalDates": {
"startDate": {
"Year": 2024,
"Month": 9,
"Day": 21
},
"endDate": {
"Year": 2024,
"Month": 9,
"Day": 29
}
},
"discounts": [
{
"categoryName": "Organic Wine",
"discountPercentage": 19
},
{
"categoryName": "White Wine",
"discountPercentage": 20
},
{
"categoryName": "Sparkling Wine",
"discountPercentage": 19
},
{
"categoryName": "Whiskey",
"discountPercentage": 17
},
{
"categoryName": "Vodka",
"discountPercentage": 23
}
]
}
]
}Example 1: Constructing a start date
This query constructs precise startDate and endDate values from nested fields using $dateFromParts, then calculates the event duration in days. It helps standardize and analyze event timelines stored in fragmented date formats.
db.stores.aggregate([
{
$match: { _id: "e6410bb3-843d-4fa6-8c70-7472925f6d0a" }
},
{
$unwind: "$promotionEvents"
},
{
$project: {
_id: 1,
startDate: {
$dateFromParts: {
year: "$promotionEvents.promotionalDates.startDate.Year",
month: "$promotionEvents.promotionalDates.startDate.Month",
day: "$promotionEvents.promotionalDates.startDate.Day"
}
}
}
}
])This query returns the following result.
[
{
"_id": "e6410bb3-843d-4fa6-8c70-7472925f6d0a",
"startDate": "2024-09-21T00:00:00.000Z"
}
]