st: Re: question about merging two data sets with non-unique identifiers.

["Michael Blasnik" <michael.blasnik@verizon.net>]

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Michael Blasnik

----- Original Message ----- 
From: "Yan Zhang" <annzhangyan@yahoo.com>
To: <statalist@hsphsun2.harvard.edu>
Sent: Saturday, April 07, 2007 8:47 AM
Subject: st: question about merging two data sets with non-unique identifiers.



> Hi, could anybody tell me how to solve the match
> problem about merging two data sets both of which have
> non-unique identifiers.
>
> For example, if DataSet A has:
> stock date
> 11 aa
> 11 bb
> 11 cc
> 33      AA
>
> and dataset B has 
> stock id
> 11 wen
> 11 fra
>
>
> After using "merge stock using "......" ", I got the
> following:
> stock id date _merge
> 11 wen aa 3
> 11 fra bb 3
> 11 fra cc 3
> 33              AA      1
>
> How could I get the results as follows as desired?
> What I want is as follows:
>
> stock id date _merge
> 11 wen aa 3
> 11 wen bb 3
> 11 wen cc 3
> 11 fra aa 3
> 11 fra bb 3
> 11 fra cc 3
> 33              AA      1
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