# Finder Methods **实例方法：** ``` exists? find find_by find_by! take take! ``` 和： ``` first first! second second! third third! fourth fourth! fifth fifth! forty_two forty_two! last last! ``` 除上述方法外，还有一些 protected 方法，但它们一般不会直接使用到。 > Rails 5 里 `find` 可以传递数组，如果没有明确排序的话，默认就使用数组里元素的顺序，这个太赞了。 --- # Agent Instructions: 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: ``` GET https://kelby.gitbook.io/rails-beginner-s-guide/activerecord_db_opertion/database_opt_relation/relation_finder_methods.md?ask= ``` The question should be specific, self-contained, and written in natural language. 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.