标签：tip ref pre des manual modify log mongo name
Name Description
$inc Increments the value of the field by the specified amount.
$mul Multiplies the value of the field by the specified amount.
$rename Renames a field.
$setOnInsert Sets the value of a field if an update results in an insert of a document. Has no effect on update operations that modify existing documents.
$set Sets the value of a field in a document.
$unset Removes the specified field from a document.
$min Only updates the field if the specified value is less than the existing field value.
$max Only updates the field if the specified value is greater than the existing field value.
$currentDate Sets the value of a field to current date, either as a Date or a Timestamp.
https://docs.mongodb.com/manual/reference/operator/update-field/
标签：tip ref pre des manual modify log mongo name
原文地址：http://www.cnblogs.com/rocky-AGE-24/p/6937971.html
