Can many to many merge join be avoided

GokhanVarol 2013-07-23 17:25:07

The leftmost 3 merge joins seem to be forcing many to many one way or the other towards right were without the leftmost would not require many to many merge joins. Can Many to many joins avoided in this plan or is it not something to worry about maybe?

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SQLkiwi 2013-07-25 12:52:26
From a quick look at the TransJoin plan, it seems the 1-M relationship is lost after the join to the EvanDemographics table. Check that join carefully to ensure you are preserving the uniqueness. The query text is truncated, and DDL for the tables and indexes has not been provided, so it's hard to give an exact answer.