[R] question about attaching data

[Pancho Mulongeni]

Hi I just would like to know,
When I have a dataframe, like this one called 'dummy'
And I attach it.
Then I run my code. 
I then update the dataframe by making changes and I still call it 'dummy'.
I run my code again.
Now dummy is at position 1 and position 2 of the search path and if I run the code again, with another version of 'dummy' it updates and eventually my search path looks like this
[1] ".GlobalEnv"        "dummy"             "dummy"            
 [4] "dummy"             "package:stats"     "package:graphics" 
 [7] "package:grDevices" "package:datasets"  "package:rcom"     
[10] "package:rscproxy"  "package:utils"     "package:methods"  
[13] "RExcelEnv"         "Autoloads"         "package:base"

I get the correct data, as the previous versions of dummy are 'masked from the search path'. What stops me from continuing this process ad infinitum?
What's the use of detaching dummy using detach()?
Thanks


Pancho Mulongeni
Research Assistant
PharmAccess Foundation
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Namibia
 
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