# 字段更新运算符

> **注意**
>
> 有关特定运算符的详细信息，包括语法和示例，请单击特定运算符以转到其参考页。

| 名称                                                                                | 描述                                   |
| --------------------------------------------------------------------------------- | ------------------------------------ |
| [`$currentDate`](/can-kao/yun-suan-fu/update-operators/field-update-operators.md) | 将字段的值设置为当前日期，即日期或时间戳。                |
| [`$inc`](/can-kao/yun-suan-fu/update-operators/field-update-operators.md)         | 将字段的值增加指定的数量。                        |
| [`$min`](/can-kao/yun-suan-fu/update-operators/field-update-operators.md)         | 仅当指定值小于现有字段值时才更新该字段。                 |
| [`$max`](/can-kao/yun-suan-fu/update-operators/field-update-operators.md)         | 仅当指定值大于现有字段值时才更新该字段。                 |
| [`$mul`](/can-kao/yun-suan-fu/update-operators/field-update-operators.md)         | 将字段的值乘以指定的数量。                        |
| [`$rename`](/can-kao/yun-suan-fu/update-operators/field-update-operators.md)      | 重命名字段。                               |
| [`$set`](/can-kao/yun-suan-fu/update-operators/field-update-operators.md)         | 设置文档中字段的值。                           |
| [`$setOnInsert`](/can-kao/yun-suan-fu/update-operators/field-update-operators.md) | 如果更新导致插入文档，则设置字段的值。对修改现有文档的更新操作没有影响。 |
| [`$unset`](/can-kao/yun-suan-fu/update-operators/field-update-operators.md)       | 从文档中删除指定的字段。                         |

译者：李冠飞

校对：


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