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Oracle Indexes

Hotsos Symposium 2017: Feb 27 – Mar 2 Dallas, Texas (I’m Afraid of Americans)

In just 3 weeks time, I’ll again have the pleasure of presenting at the awesome Hotsos Symposium in Dallas, Texas. It’s simply the best conference with regard to Oracle performance tuning anywhere. This year, I’ll be presenting on a couple of topics: New Index Features Introduced in Oracle Database 12c Release 2 Oracle Database 12c […]

12.2 Index Advanced Compression “High” Part III (I Can’t Give Everything Away)

If you like the look of the new Index Advanced Compression setting of “High” available with Oracle Database 12c Release 2 as I’ve discussed previously in Part I and Part II, well there’s a way to make this the default index compression method in your 12.2 database. Let’s begin by creating a table and explicitly […]

12.2 Index Advanced Compression “High” Part II (One Of My Turns)

In Part I, I introduced the new Index Advanced Compression default value of “HIGH”, which has the potential to significantly compress indexes much more than previously possible. This is due to new index compression algorithms that do more than simply de-duplicate indexed values within a leaf block. Previously, any attempt to completely compress a Unique […]

12.2 Index Advanced Compression “High” – Part I (High Hopes)

Oracle first introduced Advanced Compression for Indexes in 12.1 as I’ve discussed here a number of times. With Oracle Database 12c Release 2, you can now use Index Advanced Compression “High” to further (and potentially dramatically) improve the index compression ratio.  Instead of simply de-duplicating the index entries within an index leaf block, High Index […]

Oracle Database 12c Release 2: New Indexing Features – Long Identifiers (Several Species of Small Furry Animals Gathered Together in a Cave and Grooving With a Pict)

Oracle Database 12c Release 2 has now been officially released (at least on the Oracle Database Cloud and Oracle Database Exadata Express Cloud Services). In the coming weeks, I’ll be blogging about quite a number of new indexing features/capabilities/improvements that have been introduced in Oracle Database 12c Release 2. These include: Advanced Index Compression Tracking […]

Oracle 12c: Indexing JSON in the Database Part III (Paperback Writer)

In Part I and Part II, we looked at how to index specific attributes within a JSON document store within an Oracle 12c database. But what if we’re not sure which specific attributes might benefit from an index or indeed, as JSON is by it’s nature a schema-less way to store data, what if we’re not entirely sure […]

Oracle 12c: Indexing JSON in the Database Part II (Find A Little Wood)

In Part I, we looked at how you can now store JSON documents within the Oracle 12c Database. For efficient accesses to JSON documents stored in the Oracle database, we can either create a function-based index based on the JSON_VALUE function or on JSON .dot notation. These indexes are useful for indexing specific JSON attributes, […]

Oracle 12c: Indexing JSON In The Database Part I (Lazarus)

One of the very cool new features introduced in Oracle Database 12c Rel 1 is the ability to store JavaScript Object Notation (JSON) documents within the database. Unlike XML which has its own data type, JSON data can be stored as VARCHAR2, CLOB or BLOB data types, but with a JSON check constraint to ensure the […]

Next Round Of ANZ “Let’s Talk Database” Events (July/August 2016)

I’ll be presenting the next round of “Let’s Talk Database” events around Australia and NZ this winter in July/August 2016. These are free events but due to limited places have often “sold out” in the past, so booking early is recommended to avoid disappointment. All events run between 9:00am – 12:30pm and are followed by a networking lunch. We always have […]

Storing Date Values As Numbers (The Numbers)

In my last couple of posts, I’ve been discussing how storing date data in a character based column is a really really bad idea. In a follow-up question, I was asked if storing dates in NUMBER format was a better option. The answer is that it’s probably an improvement from storing dates as strings but it’s […]