Windows 10 Laptops

Teaching Oracle technology always has challenges. They’re generally large challenges because we ask students to run 4 GB Linux VM with Oracle Database 11g XE pre-configured for them. A number of the student computers aren’t up to the task of running the virtualization.

Installing VMware Workstation or Player and a 64-bit Linux operating system is the easiest way to discover a laptop that advertises itself as 64-bit when it truly isn’t. Most of the (more...)

Apple iTunes Bug

Over the years, this bug never gets fixed. I know it must irritate more people than just me. Unlike those who live in urban communities with great download speeds and relatively inexpensive Internet providers, I live in an area held hostage by expensive CableOne Internet service. Net neutrality won’t fix my issue.

The Apple iTunes bug occurs after you download a movie and the cloud symbol disappears. At first, it may appear as designed, with (more...)

Oracle 12c and PHP

This answers “How you connect PHP programs to an Oracle 12c multitenant database. This shows you how to connect your PHP programs to a user-defined Container Database (CDB) and Pluggable Database (PDB). It presupposes you know how to provision a PDB, and configure your Oracle listener.ora and tnsnames.ora files.

CDB Connection:

This assumes you already created a user-defined c##plsql CDB user, and granted an appropriate role or set of privileges to the (more...)

Type Dependent Tree

While trying to explain a student question about Oracle object types, it seemed necessary to show how to write a dependency tree. I did some poking around and found there wasn’t a convenient script at hand. So, I decided to write one.

This assumes the following Oracle object types, which don’t have any formal methods (methods are always provided by PL/SQL or Java language implementations):

CREATE OR REPLACE TYPE base_t AS OBJECT
( base_id  NUMBER  (more...)

Substitutable Columns

Oracle’s substitutable columns are interesting and substantially different than Oracle’s nested tables. The benefit of substitutable columns is that you can create one for an object type or any subtypes of that object type. Unfortunately, you can’t create the same behavior with nested tables because Oracle’s implementation of collection types are always final data types and you can’t extend their behaviors.

The Oracle Database has three types of collections. Two are SQL scoped collection types (more...)

How to install MongoDB

This post shows the yum command to install the MongoDB packages on Linux. More on setup and use will follow.

You install the MongoDB package with the following yum command:

yum install -y mongodb

You should see the following log file, which may also show a missing mirrored site:

Loaded plugins: langpacks, refresh-packagekit
cassandra/signature                                         |  819 B  00:00     
cassandra/signature                                         | 2.9 kB  00:00 !!! 
mysql-connectors-community                                  | 2.5 kB  00:00     
mysql-tools-community                                       | 2.5 kB   (more...)

Identity Columns Compared

It’s interesting to see the way different databases implement automatic numbering. Oracle Database 12c is the closest to PostgreSQL in some significant ways. However, its probably more accurate to say Oracle Database 12c copied PostgreSQL’s implementation. At least, that’s my conjecture because Oracle added a way to reset the START WITH value of the indirect sequence. However, I prefer the MySQL approach because the automatic numbering sequence is a property of the table and a (more...)

Cassandra Query Language

After installing Cassandra and reading Cassandra The Definitive Guide, it struck me that I should learn a bit more about the Cassandra Query Language (CQL). So, I setup a .bashcassandra environment file:

# Add the Java and JRE paths to the $PATH environments.
export set PATH=$PATH:/usr/lib/jvm/java-1.8.0-openjdk-1.8.0.45.x86_64:/usr/lib/jvm/java-1.8.0-openjdk-1.8.0.45.x86_64/jre

# Add the $JAVA_HOME and $JRE_HOME environment variables.
export set JAVA_HOME=/usr/lib/jvm/java-1.8.0-openjdk-1.8.0.45. (more...)

DevOps Handbook Review

DevOps: Is it a mindset or process? That’s a big question for managers because while you can’t manage a mindset, you can manage a process. DevOps is actually a framework of processes.

Some actually say DevOps is actually a lot like making a patchwork quilt. You need to design the patches before you figure out how to stitch them together. I believe this is true, and base that on my experience as a release engineer (more...)

Install Cassandra on Fedora

It was quite interesting to discover that DataStax no longer provides the DataStax Community version of Apache Cassandra or the DataStax Distribution of Apache Cassandra. Needless to say, I was quite disappointed because it means folks will get less opportunity to learn how to use Cassandra because it makes it more difficult for beginning developers.

I spent a good hour sorting through what was available and then figuring out the real requirements.

After installing and (more...)