SQLT is a tool that collects comprehensive information on all aspects of a SQL performance problem. SQL tuning experts know that EXPLAIN PLAN is only the proverbial tip of the iceberg but the fact is not well recognized by the Oracle database community, so much evangelization is necessary.
I remember the time I was trying to solve a production problem a long time ago. I did not have any tools but I was good at (more...)
What keeps you and me awake at night? When I was a consultant for a Fortune 500 company in Southern California, we were getting beaten up to prove that databases were being backed up correctly and that disaster recovery would work. The truth of the matter was that we didn’t even have an accurate list of all the databases and databases would go down for days without anybody noticing which means that they were not (more...)
Dr. Edgar Codd introduced the relational model in his 1970 paper “A Relational Model of Data for Large Shared Data Banks”—there was an earlier 1969 version but let’s not digress. The 1970 paper was reprinted in the 25th anniversary edition of the NoCOUG Journal. It’s terribly mathematical and consequently not very comprehensible to mere mortals. But his 1981 ACM Turing Award lecture is a study in contrast so I recommend it highly. You can read (more...)
NoCOUG is “the little user group that could!” As you might imagine, it requires a vast amount of work to organize a full-day users group conference and publish a printed journal every quarter. No sooner has a conference ended and a journal mailed than it is time to start work on the next conference and the next journal. But the awesome NoCOUG volunteers have pulled it off—quarter after quarter—for 30 long years. The upcoming (more...)
The most inventive thing I’ve done is a software program that I wrote for my first employer almost 30 years ago. I was a fresh-faced COBOL programmer for a software company in Bombay (now Mumbai) which had won a turnkey contract to write hundreds of COBOL reports for the very first computerization effort of the Department of Banking Operations and Development (DBOD) of the Reserve Bank of India. The report layouts had been designed by (more...)
As the editor of the NoCOUG Journal for ten years and counting, I’ve had the interview to interview some of the best minds in the Oracle world. These are a few of my favorite things they said.(read more
Once upon a time there was a very experienced database administrator who accidentally dropped a 12 TB index from a 55 TB table. The question I had was “How did he fix it?”(read more
In an interview for the NoCOUG Journal (http://www.nocoug.org/Journal/NoCOUG_Journal_200608.pdf#page=4), Steven Feuerstein was asked: “SQL is a set-oriented non-procedural language; i.e., it works on sets and does not specify access paths. PL/SQL on the other hand is a record-oriented procedural language, as is very clear from the name. What is the place of a record-oriented procedural language in the relational world?”
Steven replied: “Its place is proven: SQL is not a (more...)
It requires a vast amount of work to organize a technical conference and publish a printed journal every quarter. No sooner has a conference ended and a journal mailed than it is time to start work on the next conference and the next journal. NoCOUG has no funding from Oracle Corporation and a miniscule budget compared to the national and international user groups, but the NoCOUG volunteers have always managed to pull it off, quarter (more...)
About the book he reviewed for the August 2016 issue of the NoCOUG Journal, Brian had this to say:
“You should read this book. If you are starting out in a database-related career—which I think includes most, if not all, programming jobs—or if you are changing fields within the broader database field, the information in this book will be very helpful in the interview and on the job. I learned a great deal about things (more...)
PL/SQL offers the entire suite of structured programming mechanisms, such as condition checking, loops, and subroutines, as shown in the following figure. (read more
The Northern California Oracle Users Group (NoCOUG) is a volunteer-run 501(c)(3) organization and the longest-running Oracle users group in the world. It organizes a full-day conference every quarter and publishes a quarterly Journal. The summer conference at Chevron was the 119th quarterly conference organized by NoCOUG.(read more
P.O.I.S.E.D. is the acronym I invented for the performance tuning method described by Chris Lawson in The Art and Science of Oracle Performance Tuning; it stands for Problem, Observation, Interpretation, Solution, Execution, and Documentation.(read more
What Is a Relational Database?
Relational database theory was laid out by Codd in 1970 in a paper titled “A Relational Model for Data for Large Shared Data Banks.” His theory was meant as an alternative to the “programmer as navigator” paradigm that was prevalent in his day.
In pre-relational databases, records were chained together by pointers, as illustrated in the following figures. Each chain has an owner and zero or more members. For (more...)
Physical Data Independence means that you and I shouldn’t have to worry about implementation details such as the storage structures used to store data.(read more
Database management systems such as Oracle are the interface between users and databases. Database management systems differ in the range of features they provide, but all of them offer certain core features such as transaction management, data integrity, and security. And, of course, they offer the ability to create databases and to define their structure, as well as to store, retrieve, update, and delete the data in the databases.(read more
When you start thinking in terms such as security management, availability management, continuity management, change management, incident management, problem management, configuration management, release management, and capacity management, the business of database administration begins to make coherent sense and you become a more effective database administrator. (read more
Oracle provides a convenient virtual machine (VM) containing a complete and ready-to-use installation of Oracle Database 12c on Linux. All you need to do is to download and install the Oracle VirtualBox virtualization software and then import a ready-to-use VM.(read more
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 220.127.116.11.(read more