merge files

[Theofanis Nikolopoulos]

Hello everybody

I need to merge 3 files a main one with two small others. I have a common variable as id ( the firmcode ). However I cannot find the way to match the observations from the 2 other files to the main one.

If somebody can help, it would be very helpful.

Thanks in advance

TN

[Clyde Schechter]

There are many ways in which one might be unable to match observations between files, and they require different solutions. I doubt anyone can help you with this unless you provide example data from all three data sets and a description of what you would like the final result to look like.

To show the example data, please be sure to use the -dataex- command. If you are running version 17, 16 or a fully updated version 15.1 or 14.2, -dataex- is already part of your official Stata installation. If not, run -ssc install dataex- to get it. Either way, run -help dataex- to read the simple instructions for using it. -dataex- will save you time; it is easier and quicker than typing out tables. It includes complete information about aspects of the data that are often critical to answering your question but cannot be seen from tabular displays or screenshots. It also makes it possible for those who want to help you to create a faithful representation of your example to try out their code, which in turn makes it more likely that their answer will actually work in your data.

When asking for help with code, always show example data. When showing example data, always use -dataex-.

[Theofanis Nikolopoulos]

file 1			file 2			total file
id	var1	var2	id	var3	group	id	var1	var2	var3	group
1	65	895	1	745	1	1	65	895	745	1
5	48	652	5	653	1	5	48	652	653	1
8	35	423	15	258	1	15	22	487	258	1
14	41	542	17	945	1	17	80	632	945	1
15	22	487	20	241	1	20	49	159	241	1
17	80	632	23	277	1
20	49	159	29	123	1

That is the simple merge I wanna made. The common id of file 1 and file 2 should be added in total file, including all the other vars.

Thank you in advance
T.N.

[Clyde Schechter]

use `file1', clear
merge 1:1 id using `file2', keep(match) nogenerate

Note: I created the data sets as temporary files. Replace `file1' and `file2' in this code by the actual names of your data sets (with no `' around them).

[Theofanis Nikolopoulos]

Thank you Prof. Schechter