Hi All
What is the difference in sorting using a sort stage and sorting done inside a stages like Remove duplicate Joins etc...
Why do we have sort there when we have an explict sort stage ?
Which is more effective ?
Sort stage and Partition sort
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arunkumar1111
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Sort stage and Partition sort
Thanks and Regards
Arun
Known is a drop and Unknown is an Ocean
Arun
Known is a drop and Unknown is an Ocean
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ray.wurlod
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In all cases the same tsort operator is used.
Input link sorting constrains you to all default settings. If that's all you need it's a way to avoid cluttering up your design.
But the Sort stage gives additional choices, such as the ability to generate key change columns, the ability to perform sub-sorts only, the ability to control how much memory is allocated for sorting. My favourite is the ability to specify "don't sort" in the Sort stage, which seems counter-intuitive but prevents DataStage from inserting tsort operators where sorted input is required.
Input link sorting constrains you to all default settings. If that's all you need it's a way to avoid cluttering up your design.
But the Sort stage gives additional choices, such as the ability to generate key change columns, the ability to perform sub-sorts only, the ability to control how much memory is allocated for sorting. My favourite is the ability to specify "don't sort" in the Sort stage, which seems counter-intuitive but prevents DataStage from inserting tsort operators where sorted input is required.
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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.