Error 1:1 merge

[Ana Vasconcelos]

Hello,

I tried to merge (1:1) two datasets but I received the following message: "variables yr quarter country do not uniquely identify observations in the using data".

Example of the using data:
[CODE]
* Example generated by -dataex-. To install: ssc install dataex
clear
input int date str18 country float(earthquake_mag date1 yr1) long country_ float(year_q date2 quarter yr)
2005 "ALBANIA" 5.2 16437 2005 1 180 16437 1 2005
2005 "ALBANIA" 5.2 16437 2005 1 181 16527 2 2005
2005 "ALBANIA" 5.2 16437 2005 1 182 16618 3 2005
2005 "ALBANIA" 5.2 16437 2005 1 183 16710 4 2005
2006 "ALBANIA" 4.5 16802 2006 1 184 16802 1 2006
2006 "ALBANIA" 4.5 16802 2006 1 185 16892 2 2006
2006 "ALBANIA" 4.5 16802 2006 1 186 16983 3 2006
2006 "ALBANIA" 4.5 16802 2006 1 187 17075 4 2006
2007 "ALBANIA" 4.5 17167 2007 1 188 17167 1 2007
2007 "ALBANIA" 4.5 17167 2007 1 189 17257 2 2007
2007 "ALBANIA" 4.5 17167 2007 1 190 17348 3 2007
2007 "ALBANIA" 4.5 17167 2007 1 191 17440 4 2007
2014 "ALBANIA" 5 19724 2014 1 216 19724 1 2014
2014 "ALBANIA" 5 19724 2014 1 217 19814 2 2014

Can you help me to identify the error?
Thank you in advance.

[Rich Goldstein]

you can use the -duplicates- command to find observations that are duplicates on "yr quarter country" - depending on how many you think there are use either duplicates list or duplicates examples or duplicates tag; see

help duplicates

[Ana Vasconcelos]

Hello,

Thank you for your message. I tried to use the - report duplicates - command after the aforementioned error and I received the following message:


Duplicates in terms of yr quarter country

--------------------------------------
copies | observations surplus
----------+---------------------------
1 | 50704 0
--------------------------------------

With the command - duplicates list - I received the following information:

Duplicates in terms of all variables

(0 observations are duplicates)

There is any other way to find the problem?
Thank you in advance.

[Rich Goldstein]

it sounds as though you ran the -duplicates- command on the master data - but the error message your report in #1 is for the using data