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Add Column To Existing Index

Oracle 19c Automatic Indexing: Mixing Manual and Automatic Indexes Part II (Stay)

  In my previous post, I discussed how Automatic Indexing did not recognise there was already an existing logically equivalent manually created index and so created effectively a redundant Automatic Index. I also discussed previously how Automatic Indexing was clever enough to logically add new columns to existing Automatic Indexes if it determined such a […]

Oracle 19c Automatic Indexing: Adding Columns To Existing Automatic Indexes (2+2=5)

  In my previous post, I discussed how when the following query is run: select * from major_tom3 where code3=4 and code2=42; the Automatic Indexing process will create an index on (CODE2, CODE3) but ultimately not use the index as the CBO considers the corresponding index based execution plan too expensive. I’m going to expand […]