Confused on how to merge multiple panel datasets

[Patrick James Lim]

Hi! I am trying to merge multiple panel datasets, but I don't know which is the appropriate way and my online search hasn't lead me anywhere.

Here's an illustration of my current (long) panel datasets.

Panel A

Country	Year	Variable1	Variable2
A	2016	xx	xx
A	2015	xx	xx
A	2014	xx	xx
B	2016	xx	xx

Panel B

Country	Year	Variable3	Variable4	Variable5
A	2016	xx	xx	xx
A	2015	xx	xx	xx
B	2016	xx	xx	xx

Panel C

Country	Year	Variable6
A	2016	xx
A	2015	xx
B	2016	xx

And here's what I'm trying to achieve:

Country	Year	Variable1	Variable2	Variable3	Variable4	Variable5	Variable6
A	2016	xx	xx	xx	xx	xx	xx
A	2015	xx	xx	xx	xx	xx	xx
A	2014	xx	xx	xx	xx	xx	xx
B	2016	xx	xx	xx	xx	xx	xx
B	2015	xx	xx	xx	xx	xx	xx

*Notes

The common variables that I have are Country and Year.
I'm not trying to merge any variables or values among my Variables(1 to 6).
There is no data that I want to be lost.
xx represents any given value of the data (didn't put values so it wouldn't look messy)

Thanks!

[Rich Goldstein]

you don't show what you tried (if anything) but the help for -merge- seems pretty clear; try the following (I assume that "Panel A") is in memory; note that since you don't give filenames I have made some up:

sort country year
merge 1:1 country year using PanelB
drop _merge
sort country year
merge 1:1 country year using PanelC
drop _merge

note that, as in your example data (in the future please use -dataex-; see the FAQ), I have assumed there are no duplicates of "country year" in any file; also, I just -drop-ped _merge each time but you will see from Stata's report whether there is a problem

[Patrick James Lim]

Sorry for not posting enough information, I only tried merging them using the toolbar. However, there were duplicates on the merged data which is why I thought there's a specific process or code for merging them and the one I used was wrong. Hence, the post.
Nevertheless, I tried using the code you provided and by inspecting the data through Stata, I finally found the problem. One dataset had a space after some names which caused the problem. (Screenshot attached) I was finally able to solved the problem after editing them manually.

Thank you for your help! The code helped me save a lot of time and headache

[Rich Goldstein]

you ignored my request to show data using -dataex- and instead posted (against FAQ advice) a screen shot which I cannot read

maybe someone else can help you but based on your text you may have solved the problem? at any rate, there are easier ways to solve such issues than cleaning them up manually; in particular, see, under "help function" the help for "strtrim()"

[Patrick James Lim]

Yes I was able to solve it (with the help of your code). Once again, thank your for another tip (strtrim). It helped a lot! Many thanks

[Patrick James Lim]

Also, I'll keep the dataex in mind and will use it whenever possible in posting here. Thanks!