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@ -6729,30 +6729,33 @@ SELECT * FROM emp1 e1, emp1 e2 WHERE e1.id = e2.id AND e2.code <> e1.code; |
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-- Shuffle self-joined relations. Only in the case of iterative deletion |
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-- attempts explains of these queries will be identical. |
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CREATE UNIQUE INDEX ON emp1((id*id)); |
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explain SELECT count(*) FROM emp1 c1, emp1 c2, emp1 c3 |
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explain (costs off) |
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SELECT count(*) FROM emp1 c1, emp1 c2, emp1 c3 |
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WHERE c1.id=c2.id AND c1.id*c2.id=c3.id*c3.id; |
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QUERY PLAN |
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----------------------------------------------------------------- |
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Aggregate (cost=43.84..43.85 rows=1 width=8) |
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-> Seq Scan on emp1 c3 (cost=0.00..38.25 rows=2237 width=0) |
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QUERY PLAN |
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---------------------------------------------------------------- |
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Aggregate |
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-> Seq Scan on emp1 c3 |
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Filter: ((id IS NOT NULL) AND ((id * id) IS NOT NULL)) |
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(3 rows) |
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explain SELECT count(*) FROM emp1 c1, emp1 c2, emp1 c3 |
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explain (costs off) |
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SELECT count(*) FROM emp1 c1, emp1 c2, emp1 c3 |
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WHERE c1.id=c3.id AND c1.id*c3.id=c2.id*c2.id; |
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QUERY PLAN |
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----------------------------------------------------------------- |
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Aggregate (cost=43.84..43.85 rows=1 width=8) |
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-> Seq Scan on emp1 c3 (cost=0.00..38.25 rows=2237 width=0) |
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QUERY PLAN |
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---------------------------------------------------------------- |
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Aggregate |
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-> Seq Scan on emp1 c3 |
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Filter: ((id IS NOT NULL) AND ((id * id) IS NOT NULL)) |
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(3 rows) |
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explain SELECT count(*) FROM emp1 c1, emp1 c2, emp1 c3 |
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explain (costs off) |
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SELECT count(*) FROM emp1 c1, emp1 c2, emp1 c3 |
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WHERE c3.id=c2.id AND c3.id*c2.id=c1.id*c1.id; |
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QUERY PLAN |
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----------------------------------------------------------------- |
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Aggregate (cost=43.84..43.85 rows=1 width=8) |
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-> Seq Scan on emp1 c3 (cost=0.00..38.25 rows=2237 width=0) |
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QUERY PLAN |
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---------------------------------------------------------------- |
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Aggregate |
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-> Seq Scan on emp1 c3 |
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Filter: ((id IS NOT NULL) AND ((id * id) IS NOT NULL)) |
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(3 rows) |
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