Details
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Sub-task
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Status: Resolved
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Major
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Resolution: Invalid
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Description
Based on Szehon's observation, there is a strange extra maptask generated but not connected. Here is the query to demonstrate:
select * FROM (SELECT avg(key) as x1, value as x2 FROM src group by value) x JOIN (SELECT avg(key) as y1, value as y2 FROM src group by value) y ON (x1 = y1) JOIN (SELECT avg(key) as z1, value as z2 FROM src group by value) z ON (x1 = z1);
We shouldn't generate it in the first place.