append to file

[Pratap Pundir]

I am sure I am missing something basic here...

I want to save the memory data to a file like

save "data.dta", append

but of course, save doesn't allow append.

There is the

append using "data.dta"

command, but my understanding is that it does the opposite of what I seek - it appends contents of file into memory, while I want to append contents of memory to file.

[Dennis Lund Hansen]

The only solution I can see is something like:

tempfile datainmemory
save 'datainmemory'
use dataset.dta, clear
append using 'datainmemory'

[William Lisowski]

Dennis finds the right approach - combine the files in memory, then save the combined file. Elaborating on his approach, if it's not important to you that the data in memory be at the end of the combined files, then

append using dataset
save dataset, replace

would do the job. If the order of the data makes a difference, then it's likely there's a variable, say ID, that determines the sort order, so

append using dataset
sort ID
save dataset, replace

would do the job. If there is no variable to sort by, then

tempfile datainmemory
save `datainmemory'
use dataset, clear
append using `datainmemory'
sae dataset, replace

would do what you need, correcting Dennis's typo on the left quotation mark surrounding the local macro references -

`datainmemory'

not

'datainmemory'

[Dennis Lund Hansen]

Thank you William! Both for the elaboration and the correction, my (more or less) smart phone can not distinguish ` and ', so I had to deliver a idea rather than a fully functional code. But I should have made a disclaimer. I stand corrected and beg pardon for my misguiding :-)

[Pratap Pundir]

Thank you both.