How can I access all objects of class data.frame inside .GlobalEnv in R

Question

I have 8,000 data.frames inside my global environment (.GlobalEnv) in R, for example

head(ls(.GlobalEnv))
#[1] \"db1\" \"db2\" \"db3\"          


        

Answer 1

The simplest approach I can think of would be a basic for loop using mget.

for(df in ls(.GlobalEnv)){
    print(get(df))
}

You can then apply whatever operation you like on the mget result.

Note - this assumes the only variables in the environment are data.frames for your purposes as it doesn't discriminate A more restrictive for loop would be:

for(df in ls(.GlobalEnv)){
    if(is.data.frame(get(df))){
        print(head(get(df)))
    }
}

which just uses is.data.frame to check if the object is indeed a data.frame.