pdeffebach

Sorry i was over ambitious with starting this. Been very busy with school, but will return attention to this soon hopefully.

It seems to work with the latest version of GLMakie. But I think AlgebraOfGraphics forces a downgrade that causes the error. A more MWE ``` (jl_eAjroW) pkg> st Status `/tmp/jl_eAjroW/Project.toml`...

cc @piever since this might be more of an AoG issue

For joining in Stata, the left data frame takes precedence. I think this is the correct default, and we should do it in DataFrames.jl as well. See this [gist](https://gist.github.com/pdeffebach/545a10cc7620f3e38125fcda0f233249) describing...

Ah. Sorry for the confusion. Just did some research. It looks like Stata does not have named dataset-level dataset, for example "Date" or "Source". It's just a vector of strings....

Good point. But still, `left` taking precedence seems like a consistent default that will cause fewer headaches for users than something as destructive as getting rid of metadata.

Looking at the PR right now, is it true that if the column `:y` has metadata, then ``` transform(df, :y => f => :y) ``` will destroy that metadata?

Okay. I guess the equivalent in Stata is `replace x = ... if ...`. And we don't have that feature yet.

Stata has the command `replace` which is meant for replacing a variable. So you might say ``` replace x = missing if x == -999 ``` or even ``` replace...

I want to bring up the point again about `transform` destroying metadata when it overwrite columns. I think operations like ``` @rtransform :x = coalesce(:x, 0) ``` are more common...