Yes, the UDTF explode() is probably the easiest way to get multiple rows from 
an array. Another way would be to write your own custom script and use the 
transform clause. To generate the index of the info, you'll need the field() 
UDF, but there is currently an issue with it:

https://issues.apache.org/jira/browse/HIVE-1385


From: Viraj Bhat [mailto:[email protected]]
Sent: Tuesday, June 29, 2010 2:06 PM
To: [email protected]
Subject: Best way to create a view with index from explode ?

Hi all,
I have an input table which has 3 columns one of which is an array list,

bcookie, id, info [Schema: string, string, arraylist<map<string,string>>]

Here is a sample row

1245, 1, {[myid#id2, myage#100], [myid#id3, myage#101], [myid#id3, myage#102]}

I wanted to explode the arraylist column and create an additional column which 
represents the index of the info

bcookie, id, info, index
1245, 1, [myid#id2, myage#100], 0
1245, 1, [myid#id3, myage#101], 1
1245, 1, [myid#id3, myage#102] , 2

I was thinking of the lines of:
SELECT * FROM srctable LATERAL VIEW explode(info)... ;

Is UDTF the only way to achieve this?
Thanks Viraj

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