[jira] [Created] (IGNITE-8386) SQL: make sure PK index do not use wrapped objects

[Anton Vinogradov (Jira)]

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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