Enhance distinct set op processing
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Key: TEIID-784
URL:
https://issues.jboss.org/browse/TEIID-784
Project: Teiid
Issue Type: Feature Request
Components: Query Engine
Reporter: Steven Hawkins
Priority: Minor
The sort operation should be able to pushed for each set op child (distinct is already
eligible for pushing, but typically won't be because there's no order by). Also
for union the sorted children should be fed directly into the second phase of sorting.
All of this relies on the connector guaranteeing null ordering (TEIID-715 should be
repurposed to cover the language enhancement of nulls first|last)