Returns the hour portion of a date as a number between 0 and 23.
Changed in version 3.6.
The argument must be a valid expression that resolves to one of the following:
A document of the following form:
New in version 3.6.
The date to which the operator is applied.
<dateExpression>must be a valid expression that resolves to a Date, a Timestamp, or an ObjectID.
Optional.The timezone of the operation result.
<tzExpression>must be a valid expression that resolves to a string formatted as either an Olson Timezone Identifier or a UTC Offset . If no
timezoneis provided, the result is displayed in
Olson Timezone Identifier
"America/New_York" "Europe/London" "GMT"
+/-[hh]:[mm], e.g. "+04:45" +/-[hh][mm], e.g. "-0530" +/-[hh], e.g. "+03"
$hour cannot take a string as an argument.
sales collection with the following document:
The following aggregation uses the
$hour and other date expressions to break down the
The operation returns the following result: