> For the complete documentation index, see [llms.txt](https://docs.mongoing.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.mongoing.com/can-kao/yun-suan-fu/query-and-projection-operators/evaluation-query-operators.md).

# 评估查询运算符

> **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                      |
| -------------------------------------------------------------------------------------------------- | ----------------------- |
| [`$expr`](/can-kao/yun-suan-fu/query-and-projection-operators/evaluation-query-operators.md)       | 允许在查询语言中使用聚合表达式。        |
| [`$jsonSchema`](/can-kao/yun-suan-fu/query-and-projection-operators/evaluation-query-operators.md) | 根据给定的JSON Schema验证文档。   |
| [`$mod`](/can-kao/yun-suan-fu/query-and-projection-operators/evaluation-query-operators.md)        | 对字段的值执行模运算并选择具有指定结果的文档。 |
| [`$regex`](/can-kao/yun-suan-fu/query-and-projection-operators/evaluation-query-operators.md)      | 选择值与指定的正则表达式匹配的文档。      |
| [`$text`](/can-kao/yun-suan-fu/query-and-projection-operators/evaluation-query-operators.md)       | 执行文本搜索。                 |
| [`$where`](/can-kao/yun-suan-fu/query-and-projection-operators/evaluation-query-operators.md)      | 匹配满足JavaScript表达式的文档。   |

译者：李冠飞

校对：


---

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