How To Run previus query again and again in Oracle

We Have 3 option to run the query again in oracle

1) by "/"

2) by "R"

3) by "RUN"

• OPTION 1) By "/" Character..

 

•  option 2) By Writing "R" 

• OPTION 3) By Writing "RUN"

There Is no Difference between "R" and "RUN" both are same but when we write "/" it doesn't show Query but when we write "R" or "RUN" it shows the Query....!!!!

how to Clear All previous Query output in Oracle Command prompt

To Clear the Output We Have command name "CL SCR" Which is Used to Clear the output