Somebody thought it was nice to show how to drop object type dependents in Oracle Database 11g, but they thought I should show how you discover dependent object types first. More or less, they were concerned how they discover type dependents when they raise the following error:
DROP TYPE item_object
ERROR at line 1:
ORA-02303: cannot DROP OR REPLACE a TYPE WITH TYPE OR TABLE dependents
They had a (more...)
During my time off I noted a bunch of information to dig into later, and I thought I'd make some notes as I go - see if you missed any interesting news.
I'll do a separate post for noteable blog posts.
Oracle REST Data Services
As Dimitri announced here
, Oracle has another product "formerly known as" - this time it's the APEX Listener.
Now known by what I think is a name that may also (more...)
email@example.com > select banner from v$version;
Oracle Database 12c Enterprise Edition Release 18.104.22.168.0 - 64bit Production
PL/SQL Release 22.214.171.124.0 - Production
CORE 126.96.36.199.0 Production
TNS for Linux: Version 188.8.131.52.0 - Production
NLSRTL Version 184.108.40.206.0 - Production
firstname.lastname@example.org > select value from nls_database_parameters where parameter='NLS_CHARACTERSET';
email@example.com > ! (more...)
Chris Saxon posted a nice quiz regarding a pitfall when creating tables with VARCHAR2-columns: when you are not explicit in specifying the length-semantics ( CHAR or BYTE ), a session parameter, which may vary, is used.
This is a short follow-up of his story, which shows more pitfalls when creating views and selecting from those.
We end up in a structure which can – by definition – contain only 1 byte, but actually shows containing (more...)
As covered in my new Oracle Database 12c PL/SQL Programming book (publisher’s satisfied), you can evolve object types. That means you can change a base object type and the change cascades through dependents. Somebody asked how to remove an object type chain without appending the
It’s quite easy if you understand writing a recursive function in PL/SQL, as done here:
There continues to be a disproportionate amount of hype around 'NoSQL' data stores. By disproportionate I mean 'completely and utterly out of scale with the actual problems of the vast majority of companies'. I wrote before about 'how NoSQL became more SQL'. The point I made there is now more apparent the more I work with companies on Big Data challenges.
There are three worlds of data
This year, from June 22 - June 26, the best convention in the world, ODTUG’s KScope14 will be held in Seattle, Washington. I am already looking forward to meeting some ‘old’ friends again, creating new friends and seeing some of the best content by presenters from all over the world.
Some of the presentations I am looking forward to:
In the Developer’s Toolkit track:
After writing nine books, it’s always great when the author copies arrive. That’s when I know the process is complete. Friday, my twelve copies of the Oracle Database 12c PL/SQL Programming book in two boxes of six each. The book is also available online at Amazon.com.
The book qualifies all the Oracle 12c new SQL and PL/SQL features. I added review sections and mastery questions to each chapter, and expanded examples and (more...)
So I wrote about why your Hadoop project will fail so I think its only right that I should follow up with some things that you can do to actually make the Big Data project you take on succeed. The first thing you need to do is stop trying to make 'Big Data' succeed and instead start focusing on how you educate the business on the value of information and then work out how to deliver new (more...)
Here is a restriction of the cardinality hint in conjunction with the materialize-hint ( note: both are undocumented but sometimes of great use ):
we cannot tell the optimizer in the outer query ( the one that uses the materialized subquery ) about the cardinality of the materialization, this can only – and then not always – be done within the materializing query.
The example to show that is stolen from Tom Kyte’s Presentation S13961_Best_Practices_for_Managing_Optimizer_Statistics_Short. (more...)
It’s sometimes amazing, how many bugs there are still with elementary SQL.
Here is one concerning updatable views:
firstname.lastname@example.org > create table t ( v varchar2(30) );
email@example.com > create view v as
2 select v as dontdothatman, v as canbelostwheninserted
3 from t;
firstname.lastname@example.org > insert /* this is fine */ into v
2 values('fine', 'fine');
1 row created.
email@example.com > select * from v;
On the twelfth day of Christmas, my true love gave to me Twelve drummers drumming. The relational camp put productivity, ease-of-use, and logical elegance front and center. However, the mistakes and misconceptions of the relational camp prevent mainstream database management systems from achieving the performance level required by modern applications. For example, Dr. Codd forbade […]
Ok so Hadoop is the bomb, Hadoop is the schizzle, Hadoop is here to solve world hunger and all problems. Now I've talked before about some of the challenges around Hadoop for enterprises but here are six reasons that Information Week is right when it says that Hadoop projects are going to fail more often than not.
1. Hadoop is a Java thing not a BI thing
The first is the most important
On the eleventh day of Christmas, my true love gave to me Eleven pipers piping. Over a lifespan of four and a half decades, the relational camp made a series of strategic mistakes that made NoSQL and Big Data possible. The mistakes started very early. The biggest mistake is enshrined in the first sentence of […]
On the tenth day of Christmas, my true love gave to me Ten lords a-leaping. The topic of Big Data is often encountered when talking about NoSQL so let’s give it a nod. In 1998, Sergey Brin and Larry Page invented an algorithm for ranking web pages (The Anatomy of a Large-Scale Hypertextual Web Search […]
On the ninth day of Christmas, my true love gave to me Nine ladies dancing. NoSQL databases can be classified into the following categories: Key-value stores: The archetype is Amazon Dynamo of which DynamoDB is the commercial successor. Key-value stores basically allow applications to “put” and “get” values but each (more...)
On the seventh day of Christmas, my true love gave to me Seven swans a-swimming. As we discussed on Day One, NoSQL consists of “disruptive innovations” that are gaining steam and moving upmarket. So far, we have discussed functional segmentation (the pivotal innovation), sharding, asynchronous replication, eventual consistency (resulting from (more...)
On the sixth day of Christmas, my true love gave to me Six geese a-laying. The final hurdle was extreme performance, and that’s where the Dynamo developers went astray. The Dynamo developers believed that the relational model imposes a “join penalty” and therefore chose to store data as “blobs.” (more...)
On the fifth day of Christmas, my true love gave to me Five golden rings. By now, you must be wondering when I’m going to get around to explaining how to create a NoSQL database. When I was a junior programmer, quite early in my career, my friends and I were assigned (more...)