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pig script similar to select from not in in SQL
Chan, Tim 2012-01-24, 21:47
I would like to generate a set of data that represents the items not found in another set. How would I do this using Pig?
I'm thinking I would do an outer join and then filter off the items that were matched.
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Chan, Tim 2012-01-24, 21:47
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Re: pig script similar to select from not in in SQL
Jonathan Coveney 2012-01-24, 21:53
I would do the following (obviously this is a bit shorthand):
a = load 'data1'; b = load 'data2'; c = cogroup a by $0, b by $0; d = filter c by IsEmpty(b);
d would be a relation with only the keys and their corresponding rows which exist in a
2012/1/24 Chan, Tim <[EMAIL PROTECTED]>
> I would like to generate a set of data that represents the items not found > in another set. > How would I do this using Pig? > > I'm thinking I would do an outer join and then filter off the items that > were matched. > >
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Jonathan Coveney 2012-01-24, 21:53
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RE: pig script similar to select from not in in SQL
Chan, Tim 2012-01-24, 22:07
Thanks Jonathan.
I did the following:
a = load 'data1'; b = load 'data2'; c = join a by $0 left outer, b by $0; d = filter c by $1 is null; e = foreach d generate $0; ________________________________________ From: Jonathan Coveney [[EMAIL PROTECTED]] Sent: Tuesday, January 24, 2012 1:53 PM To: [EMAIL PROTECTED] Subject: Re: pig script similar to select from not in in SQL
I would do the following (obviously this is a bit shorthand):
a = load 'data1'; b = load 'data2'; c = cogroup a by $0, b by $0; d = filter c by IsEmpty(b);
d would be a relation with only the keys and their corresponding rows which exist in a
2012/1/24 Chan, Tim <[EMAIL PROTECTED]>
> I would like to generate a set of data that represents the items not found > in another set. > How would I do this using Pig? > > I'm thinking I would do an outer join and then filter off the items that > were matched. > >
+
Chan, Tim 2012-01-24, 22:07
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