Oracle Sort Join

Sort join is the first operation of the “Sort Merge Join”. Before Oracle joins two row sources, both row sources have to be in order. If required, Oracle does a sort. The name is a bit misleading. All it does is a sort on the join key.

 

The “Sort Merge Join” consists of two steps:

• Sort join operation. Both the inputs are sorted on the join key.
• Merge join operation. The sorted lists are merged.

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