Large Numbers Of Virtual Columns can Result in Slow Query Parsing
Last updated on SEPTEMBER 11, 2016
Applies to:Oracle Database - Enterprise Edition - Version 220.127.116.11 and later
Oracle Database - Standard Edition - Version 18.104.22.168 and later
Oracle Database - Personal Edition - Version 22.214.171.124 and later
Information in this document applies to any platform.
A query with a large number of references to tables having a large number of virtual columns parses slowly.
Consider the following case, where one table (t) with 50 virtual columns is referenced 500 times in one query:
This can happen even if the virtual columns are never referenced in the query, as above.
"Computed" columns maintained by a trigger are replaced by GENERATED ALWAYS AS columns.
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