| From: | Vitaliy Garnashevich <vgarnashevich(at)gmail(dot)com> |
|---|---|
| To: | pgsql-general(at)postgresql(dot)org |
| Subject: | Number of rows returned by Sort node |
| Date: | 2018-01-09 15:20:23 |
| Message-ID: | 6979dc4e-a7d1-993d-f2a4-bcdaff05106d@gmail.com |
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| Lists: | pgsql-general |
Hi,
How, according to EXPLAIN ANALYZE, the Sort node could return more rows
as output (rows=767662), than it had for input from its child node
(rows=135627)?
-> Merge Join .... (actual time=1977.388..333626.072 rows=725757 loops=1)
-> Index Scan using .... (actual time=0.013..312144.441
rows=49176765 loops=1)
-> Sort .... (actual time=1977.363..2274.092 rows=767662 loops=1)
-> Hash Left Join .... (actual time=97.123..1887.956
rows=135627 loops=1)
(full plan attached, PostgreSQL 9.3)
Regards,
Vitaliy
| Attachment | Content-Type | Size |
|---|---|---|
| plan.txt | text/plain | 5.4 KB |
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