DSXchange

I am joining two datasets using the join stage, to sort the incoming data which of the two is best:

1) In link sort
2) using 2 sort stages explicitly on both links

It would be of great help if the reason is specified.

Thanks..........

Both are the same as far as only sorting (using datastage sort) is concerned as both will insert a tsort operator.

but an explicit sort stage give you more options than inlink sort like
getting key change column, liberty to select the utility used for sorting (Datastage/Unix), It can dump stats and also you can restrict the memory usage from the stage itself.

My concern is only sorting the data, no other options required

zulfi123786 wrote:My concern is only sorting the data, no other options required

Then i don't think it makes any difference during execution but I prefer explicit sort stage.

Performance wise Inline sort is best compare to explicit sort stages.

srinivas.g wrote:Performance wise Inline sort is best compare to explicit sort stages.

Based on what? Under the covers they're both the same tsort operator.

could you please mention which document of datastage discusses tsort.....

I didnot find anything mentioned in the DS parallel job developer guide saying the sort stage inserts a tsort operator.

You'd probably have to go back to an ORCHESTRATE manual for that. Check the Generated OSH tab in the job, you'll see them there.

srinivas.g wrote:Performance wise Inline sort is best compare to explicit sort stages.

I disagree 100%. But I'd be interested to hear your reasons.

Two reasons an explicit Sort stage is better (and can be better for performance):

• you can control the amount of memory allocated
  
  you can generate key change indicators