Re: Batch update of indexes - Mailing list pgsql-hackers

From Konstantin Knizhnik
Subject Re: Batch update of indexes
Date
Msg-id 56A11652.60103@postgrespro.ru
Whole thread Raw
In response to Re: Batch update of indexes  (Simon Riggs <simon@2ndQuadrant.com>)
List pgsql-hackers


On 21.01.2016 10:14, Simon Riggs wrote:
On 21 January 2016 at 06:41, konstantin knizhnik <k.knizhnik@postgrespro.ru> wrote:
 
Certainly for B-Tree we can organize insert buffer (or pending list) as sorted array or also as a tree.
But in both case complexity of search in this buffer will be O(log(N)), not O(1).

You are right; search within this buffer is O(log(N)). But we can test whether we need to search in the buffer at all with O(1).

Only if records are inserted in key ascending order...
But usually we need to maintain more than once index and and for them it is not true.


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Simon Riggs                http://www.2ndQuadrant.com/
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Konstantin Knizhnik
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The Russian Postgres Company 

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