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Greetings Experts,
Can you please explain the following
The “union” command can be used to break up a large sql process or statement into several smaller sql processes or statements, which would run in parallel. But these could then cause spoolspace limit problems. “Union all” executes the sql’s single threaded


I have a quesion.

In case of huge data volume which one from below wil be better?


Insert into A






from B