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@ -423,7 +423,7 @@ EXPLAIN SELECT * FROM pgbench_accounts WHERE filler LIKE '%x%'; |
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Append</literal> node can have both partial and non-partial child plans. |
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Append</literal> node can have both partial and non-partial child plans. |
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Non-partial children will be scanned by only a single process, since |
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Non-partial children will be scanned by only a single process, since |
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scanning them more than once would produce duplicate results. Plans that |
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scanning them more than once would produce duplicate results. Plans that |
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involve appending multiple results sets can therefore achieve |
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involve appending multiple result sets can therefore achieve |
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coarse-grained parallelism even when efficient partial plans are not |
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coarse-grained parallelism even when efficient partial plans are not |
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available. For example, consider a query against a partitioned table |
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available. For example, consider a query against a partitioned table |
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that can only be implemented efficiently by using an index that does |
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that can only be implemented efficiently by using an index that does |
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