如何在rails中使用like子句查询？

我想在搜索关键字时获得数据的json格式，所以我使用LIKE子句和这样的查询

"select * from employees where fname like ? or mname like ? or lname like ? or username like ? or id like ?", str, str, str, str, str 

但我想用rails编写代码。 我的控制器中有这个代码

 def showemployees str = params[:str] render json: @employee = Employee.where(Employee.employees[:fname].matches("%#{str}%")) or (Employee.employees[:mname].matches("%#{str}%")) or (Employee.employees[:lname].matches("%#{str}%")) or (Employee.employees[:id].matches("%#{str}%")) end 

这个代码在我的config / routes.rb中

 get 'employees/showemployees' root :to => 'employees#new' resources :employees post 'employees/update_info' 

当我输入这个， http：// localhost：3000 / employees / showemployees？str = samplename ，该记录的json格式应该出现但我收到此错误消息

 undefined method `employees' for # app/controllers/employees_controller.rb:6:in `showemployees' 

第6行有这个代码

 render json: @employee = Employee.where(Employee.employees[:fname].matches("%#{str}%")) or 

Answer 1

您可以链接查询的位置，但这个AND每个查询结果

 Employee.where('fname LIKE ?', "%#{str}%").where('lname LIKE ?', "%#{str}%").where('mname LIKE ?', "%#{str}%").where('username LIKE ?', "%#{str}%").where('id LIKE ?', "%#{str}%") 

或使用OR子句

 Employee.where('fname LIKE ? OR lname LIKE ? OR mname', "%#{str}%", "%#{str}%", "%#{str}%")