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- $dateToString (aggregation)
$dateToString (aggregation)¶
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Definition¶
-
$dateToString
¶ New in version 3.0.
Converts a date object to a string according to a user-specified format.
The
$dateToString
expression has the following syntax:The
$dateToString
takes a document with the following fields:Field Description format
The date format specification. <formatString>
can be any string literal, containing 0 or more format specifiers. For a list of specifiers available, see Format Specifiers.date
The date to convert to string. <dateExpression>
can be any expression that evaluates to a date. For more information on expressions, see Expressions.
Format Specifiers¶
The following format specifiers are available for use in the
<formatString>
:
Specifiers | Description | Possible Values |
---|---|---|
%d |
Day of Month (2 digits, zero padded) | 01 -31 |
%G |
Year in ISO 8601 format New in version 3.4. |
0000 -9999 |
%H |
Hour (2 digits, zero padded, 24-hour clock) | 00 -23 |
%j |
Day of year (3 digits, zero padded) | 001 -366 |
%L |
Millisecond (3 digits, zero padded) | 000 -999 |
%m |
Month (2 digits, zero padded) | 01 -12 |
%M |
Minute (2 digits, zero padded) | 00 -59 |
%S |
Second (2 digits, zero padded) | 00 -60 |
%u |
Day of week number in ISO 8601 format (1-Monday, 7-Sunday) New in version 3.4. |
1 -7 |
%U |
Week of year (2 digits, zero padded) | 00 -53 |
%V |
Week of Year in ISO 8601 format New in version 3.4. |
01 -53 |
%w |
Day of week (1-Sunday, 7-Saturday) | 1 -7 |
%Y |
Year (4 digits, zero padded) | 0000 -9999 |
%% |
Percent Character as a Literal | % |
Example¶
Consider a sales
collection with the following document:
The following aggregation uses the $dateToString
to
return the date
field as formatted strings:
The operation returns the following result: