Vladimir Ozerov created IGNITE-8386:
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Summary: SQL: make sure PK index do not use wrapped objects
Key: IGNITE-8386
URL: https://issues.apache.org/jira/browse/IGNITE-8386
Project: Ignite
Issue Type: Task
Components: sql
Affects Versions: 2.4
Reporter: Vladimir Ozerov
Fix For: 2.6
Currently PK may be built over the whole {{_KEY}} column, i.e. the whole binary
object. This could happen in two cases:
1) Composite PK
2) Plain PK but with {{WRAP_KEY}} option.
This is critical performance issue for two reasons:
1) This index is effectively useless and cannot be used in any sensible
queries; it just wastes space and makes updates slower
2) Binary object typically has common header bytes what may lead to excessive
number of comparisons during index update.
To mitigate the problem we need to ensure that index is *never* built over
{{_KEY}}, Instead, we must always extract target columns and build normal index
over them.
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