Hi Everybody
I am having a wired Issue. In my job I am using close to 5 joins
basically i have a driver tables and i am joining to another table on key1 before joining i am hashing on key 1 on both the links .now from the joined table i get key2 using this key2 i join to another table based on key2.Before i am joining i am hashing on key2 ,But every time i run it i see different out put counts ......on all the remaining joins i am using partitioning same........can any one tell me why i am getting different count
Thanks
Hashing Issue
Moderators: chulett, rschirm, roy
Hi,
You have to clear the previous partitioning before giving it to a new partition. In the second join which is on key2, you should clear the previous partiton which is out of key1. Also the next consecutive joins is also based on key2 alone, if so then use same partition else clear in 3rd join and give appropriate keys in partition.
Thanks.
You have to clear the previous partitioning before giving it to a new partition. In the second join which is on key2, you should clear the previous partiton which is out of key1. Also the next consecutive joins is also based on key2 alone, if so then use same partition else clear in 3rd join and give appropriate keys in partition.
Thanks.
Gopinath
Yep I am doing that ..still i have any issue ..Gopinath wrote:Hi,
You have to clear the previous partitioning before giving it to a new partition. In the second join which is on key2, you should clear the previous partiton which is out of key1. Also the next consecutive joins is also based on key2 alone, if so then use same partition else clear in 3rd join and give appropriate keys in partition.
Thanks.
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Join stage (and certain others) mandatorily require that inputs be identically sorted and partitioned, in the case of the Join stage on the specified join keys. Usually this implies the Hash partitioning algorithm but, for a single integer key, the modulus partitioning algorithm may prove more efficient.
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Any contribution to this forum is my own opinion and does not necessarily reflect any position that IBM may hold.
Any contribution to this forum is my own opinion and does not necessarily reflect any position that IBM may hold.