Suboptimal Execution Plan When OR Expansion is Rejected due to LOB
(Doc ID 2887904.1)
Last updated on APRIL 17, 2023
Applies to:
Oracle Database - Enterprise Edition - Version 12.2.0.1 to 19.16.0.0.0 [Release 12.2 to 19]Information in this document applies to any platform.
Symptoms
For SQL Query with LOB Column, "OR Expansion" is rejected, producing Sub-optimal Execution plan.
When "_optimizer_cbqt_or_expansion" is disabled it produces good plan.
When Cost Based OR Expansion(CBQT_ORE) is enabled, the Legacy ORE (i.e. Concatenation ) does not get applied.
Changes
Cause
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In this Document
| Symptoms |
| Changes |
| Cause |
| Solution |
| References |