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https://issues.apache.org/jira/browse/IGNITE-4150?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Vladimir Ozerov updated IGNITE-4150:
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Description:
Consider the following query:
{code}
SELECT * FROM table
WHERE a = ? AND b IN (?, ?)
{code}
If there is an index {{(a, b)}}, it will not be used properly: only column
{{a}} will be used. This will leads to multiple unnecessary comparisons.
Most obvious way to fix that - use temporary table and {{JOIN}}. However, this
approach doesn't work well when there are multiple {{IN}}'s.
Proper solution would be to hack deeper into H2.
was:
Consider the following query:
{code}
SELECT * FROM table
WHERE a = ? AND b IN (?, ?)
{code}
If there is an index {{(a, b)}}, it will not be used properly: only column
{{a}} will be used. This will leads to multiple unnecessary comparisons.
Most obvious way to fix that - use temporary table and {{JOIN}}. However, this
approach doesn't work well when there are multiple {{IN}}s.
Proper solution would be to hack deeper into H2.
> B-Tree index cannot be used efficiently with IN clause.
> -------------------------------------------------------
>
> Key: IGNITE-4150
> URL: https://issues.apache.org/jira/browse/IGNITE-4150
> Project: Ignite
> Issue Type: Task
> Components: SQL
> Affects Versions: 1.7
> Reporter: Vladimir Ozerov
> Labels: performance
> Fix For: 2.0
>
>
> Consider the following query:
> {code}
> SELECT * FROM table
> WHERE a = ? AND b IN (?, ?)
> {code}
> If there is an index {{(a, b)}}, it will not be used properly: only column
> {{a}} will be used. This will leads to multiple unnecessary comparisons.
> Most obvious way to fix that - use temporary table and {{JOIN}}. However,
> this approach doesn't work well when there are multiple {{IN}}'s.
> Proper solution would be to hack deeper into H2.
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