> For the complete documentation index, see [llms.txt](https://wiki.clay-wangzhi.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://wiki.clay-wangzhi.com/17-redis/17.4-shu-ju-ku-cao-zuo/17.4.2-jian-ming-ling.md). # 17.4.2 键命令 * 查找键 参数⽀持正则表达式 ``` keys pattern ``` * 判断键是否存在， 如果存在返回1，不存在返回0 ``` exists key ``` * 查看键对应的value的类型 ``` type key ``` * 删除键 ``` del key1 key2 ... ``` * 设置过期时间 以秒为单位，如果没有指定过期时间则⼀直存在，直到使⽤DEL移除 ``` expire key seconds ``` * 查看有效时间 以秒为单位 ``` ttl key ``` --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter: ``` GET https://wiki.clay-wangzhi.com/17-redis/17.4-shu-ju-ku-cao-zuo/17.4.2-jian-ming-ling.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.