Element Query Operators元素查询运算符

Note

For details on specific operator, including syntax and examples, click on the specific operator to go to its reference page.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。

Name名称Description描述
$exists Matches documents that have the specified field.匹配具有指定字段的文档。
$type Selects documents if a field is of the specified type.如果字段为指定类型，则选择文档。