Believe it or Not: Converting an Inner Join to an Outer Join to improve performance

The cost-based optimizer tries to merge views whenever possible but sometimes we ma y want to override this behavior; that is, we may want the optimizer to push predicates into the view instead of merging the view into the main query. If the main query performs an inner join to the view, it becomes necessary to convert the inner join to an outer join if the database version is less than 12.1.0.2.(read more)

Happy Hinting: Undocumented PUSH_PRED hint variation

There isn’t a documented method of controlling which specific predicate to push.; it appears that the decision is left to the cost-based optimizer. However there is an undocumented method. Both the PUSH_PRED and NO_PUSH_PRED hints accept an optional second parameter(read more)

The Oracle Database professional I admire most

Carlos Sierra spent 17 years in the SQL performance group of Oracle Support. He couldn’t move a mountain nor pull down a big oak tree. But Carlos Sierra became a mighty big man by putting all the knowledge he gained during that time into a wonderful tool called “SQLT.”(read more)

Point to Ponder: The most important insight about Oracle Database upgrades?

Someone recently gave me an insight with which you would probably agree with: If query performance is satisfactory before and after the upgrade, then business users are unlikely to complain if new optimizer features are not being used after the upgrade.(read more)

Major and Minor keys in Oracle NoSQL Databsae

Oracle NoSQL Database uses Major and Minor key values to influence record co-location. Records are stored based on the hash of the major key, so all of the records with the same major key will be co-located on the same server.

A JSON document could be divided into sub-parts, with each sub-part having a different minor key. For example, customer meta data could be stored in the main customer record, transactions in a different record, (more...)

Oracle Cloud v/s Amazon Cloud?

A few years ago, I taught an online class in Oracle database administration for the University of Washington. Every student was given their own virtual machine for the duration of the class, courtesy of Amazon. It was ridiculously simple to clone, start, stop, and destroy virtual machines using the Amazon CLI (command line interface). All students had full SSH and SQL*Net access to their virtual machines in the Amazon cloud. At that time, Oracle had (more...)

NoSQL workshop at Oracle user group conference

Oracle NoSQL Database has been regularly featured at the conferences of the Northern California Oracle Users Group. But, at its most recent conference, the Northern California Oracle Users Group dared to play outside the Oracle sandbox with a whole day NoSQL workshop featuring three Oracle competitors: MongoDB, Couchbase, and Cassandra.(read more)

The best idea since 1992: Putting the C into ACID (We need your vote)

Oracle Rdb (only available for the VMS platform) supports SQL-92 assertions (http://community.hpe.com/hpeb/attachments/hpeb/itrc-149/22979/1/15667.doc) so why not Oracle Database? Let’s put the “C” into “ACID.”(read more)

When SQLT is not enough

A SQLT report has all kinds of pertinent information including—to name just a few—optimizer settings, indexes, statistics, plan history, and view definitions. However, sometimes a SQLT report is not enough to solve a SQL performance problem.(read more)

How is data modeled in NoSQL?

The important thing to understand is the data does not change just because it is managed differently. If the data does not change, then the entities and the relationships contained in the data cannot change either. The entities and the relationships between them have not changed since the dawn of time. They were the same in the days of network database management systems which came before relational database management systems, they stayed the same when (more...)

Why should Oracle Database professionals care about NoSQL and where to start?

Oracle Corporation openly admits that NoSQL database management systems have the performance advantage over relational database management systems “when data access is ‘simple’ in nature and application demands exceed the volume or latency capability of traditional data management solutions.” Database professionals should therefore look seriously at NoSQL technology.(read more)

Why Brian Hitchcock and I (probably) know more about Oracle Database than you‏

Brian Hitchcock’s secret is simple. For twelve years, he has been reading books on Oracle Database. And taking extensive notes. And publishing them in the NoCOUG Journal. My secret is simple. For twelve years, I have been reading the extensive book notes that Brian has been publishing in the NoCOUG Journal. I’m the editor of the NoCOUG Journal but that’s not the point. It’s that simple. (read more)

NoCOUG changes its name (Happy April Fools Day)‏

The board members of NoCOUG meets in closed session to discuss the continuing decline in memberships and conference attendance.(read more)

The company that is most responsible for NoSQL is not Amazon

The company that is most responsible for NoSQL is not Amazon but Oracle Corporation.(read more)

The First and Last Word on NoSQL

Amazon had the first word on NoSQL but the creator of relational theory, Dr. E. F. Codd, gets the last word.(read more)

A complete family of data management products that solve all use cases

Oracle has a complete family of data management products that solve all use cases.(read more)

Making SQL Great Again (SQL is Huuuuuge) Part V

Lightly-edited partial transcript of a panel discussion titled “Making SQL Great Again (SQL is Huuuuuge)” at YesSQL Summit 2016 organized by the Northern California Oracle Users Group (NoCOUG) at Oracle Corporation’s headquarters in Redwood City, California. NoCOUG is the longest-running and most-active Oracle users group in the world. An individual membership only costs $95 and entitles the member to free admission to the four consecutive quarterly NoCOUG conferences (one-day events) that follow the membership’s start (more...)

Making SQL Great Again (SQL is Huuuuuge) Part IV

Lightly-edited partial transcript of a panel discussion titled “Making SQL Great Again (SQL is Huuuuuge)” at YesSQL Summit 2016 organized by the Northern California Oracle Users Group (NoCOUG) at Oracle Corporation’s headquarters in Redwood City, California. NoCOUG is the longest-running and most-active Oracle users group in the world. An individual membership only costs $95 and entitles the member to free admission to the four consecutive quarterly NoCOUG conferences (one-day events) that follow the membership’s start (more...)

Making SQL Great Again (SQL is Huuuuuge) Part VI

Lightly-edited partial transcript of a panel discussion titled “Making SQL Great Again (SQL is Huuuuuge)” at YesSQL Summit 2016 organized by the Northern California Oracle Users Group (NoCOUG) at Oracle Corporation’s headquarters in Redwood City, California. NoCOUG is the longest-running and most-active Oracle users group in the world. An individual membership only costs $95 and entitles the member to free admission to the four consecutive quarterly NoCOUG conferences (one-day events) that follow the membership’s start (more...)

SQL is Huuuuuuuge (Making SQL Great Again) Part I

Lightly-edited partial transcript of a panel discussion titled “Making SQL Great Again (SQL is Huuuuuge)” at YesSQL Summit 2016 organized by the Northern California Oracle Users Group (NoCOUG) at Oracle Corporation’s headquarters in Redwood City, California. NoCOUG is the longest-running and most-active Oracle users group in the world. An individual membership only costs $95 and entitles the member to free admission to the four consecutive quarterly NoCOUG conferences (one-day events) that follow the membership’s start (more...)