The PyGame library is a wonderful tool for building games with Python. It lets you accomplish a great deal by simply managing events. You need to understand how to use Python functions, modules, and events to build games with this Python library.
You can download and install the PyGame library with the yum utility like this:
yum install -y pygame
It should generate the following list when you install it as the root user:
It’s always a challenge when you want to build your own Oracle SQL Tools. I was asked how you could synchronize multiple cursors into a single source. The answer is quite simple, you write an Oracle object type to represent a record structure, an Oracle list of the record structure, and a stored function to return the list of the record structure.
For this example, you create the following table_struct object type and a table_list collection type:
Sometime formal programming documentation is less than clear. At least, it’s less than clear until you’ve written your first solution. The Modules section of the Python language is one of those that takes a few moments to digest.
It’s always interesting to explain a new programming language to students. Python does presents some challenges to that learning process. I think for loop can be a bit of a challenge until you understand them. Many students are most familiar with the traditional for loop like Java:
The instance that I’ve built for my students in a Fedora VM is quite stable except for one feature. The feature is the hibernation process of the base operating system. Sometimes when the base operating system hibernates, it causes the Oracle shared memory segment to fail. When that happens you get the following error:
I thought this illustration was an interesting view of Oracle Database 12c’s Multitenant Architecture. It posted on ToadWorld.com today in a new article by Deiby Gomez and I thought it might be interesting for others.
As does seem to occur from time-to-time, I’m out there in the weeds again and sorting out a solution that fits a customer’s need. They wanted to know if they could write Oracle EBS 12.2 Concurrent Manager Programs in Ruby. They don’t want to write Java.
A question popped up, which I thought was interesting. How can you create a DB_LINK in Oracle without the DBA changing the tnsnames.ora file? It’s actually quite easy, especially if the DBA sets the TNS address name the same as the instance’s service name or in older databases SID value.
If you’re reading this post, you most likely are trying to run the Oracle Database 11g or 12c runInstaller program, and it’s failing a critical dependency check and displaying an error like the one below. If so, choose n because if you choose y it won’t launch the Oracle Installer.
Installing any Oracle database is tedious, but the installing the pre-requisites can be tedious. This post tries to simplify the process by creating a single prereq.sh file for all the pre-requisite libraries. The file should contain the following:
This post shows you how to add the menu option and GUI to set users and groups. It’s quite a bit easier than mastering all the command-line syntax. It makes setting up the required user and group accounts for an Oracle Enterprise or MySQL database solution much easier.
You add the utility by calling the yum (Yellowdog Updater, Modified) utility like this:
Occasionally, my students loose their network connection when copying their virtual machines. This article shows you how to rebuild your Internet connection.
The first step requires you to identify the port number on your host operating system, which is typically Windows OS or Mac OS X. You can find that by running the following search from a Mac OS X Terminal session or Windows OS Command session.
If you’re on the Mac OS X, you launch a Terminal session and then use the sudo command to open a shell as the root super user, like this:
What happens when you can’t get a PL/SQL Web Toolkit to work because it only prints to a web page? That’s more tedious because any dbms_output.put_line command you embed only prints to a SQL*Plus session. The answer is quite simple, you create a test case and test it inside a SQL*Plus environment.
Here’s a sample web page that fails to run successfully …
While SQL Developer installs with a dbms_output view, some organizations close it before they distribute images or virtual machine (VM) instances. This post shows you how to re-enable the Dbms Output view for SQL Developer.
It was quite annoying to find that TurboTax couldn’t send me a text message to confirm my order of a second state. However, I made the mistake of clicking the “Confirm my account a different way (takes longer)” radio button to get to their web page.
After I got two-step verification enabled on their web site, now it’s impossible to order the second state software. It appears that once you click that button, the software writes it to a file and never prompts you for text, email, or other verification. That seems like a bug to me, what do you think?
During the holidays, I check salaries for my students and the IT industry overall. I’m never surprised by the reality, after all salaries pay for return on skills and effort. Here’s my annual look, which some may find unkind but reality is seldom kind.
Before looking at IT salaries, it seems like a good opportunity to first look at the overall job market for Millennials in the United States. AOL provides a great graphic of the median income for Millennials (those born between 1981 and 1997), which is $18,000 to $43,000 a year:
I posted earlier in the year how to configure a Fedora instance to test PHP code on a local VM. However, I’ve got a few questions on how to find those posts. Here’s a consolidation with links on those steps:
Often, the biggest problem with regular expressions is that those who use them sometimes don’t use them correctly. A great example occurs in the Oracle Database with the REGEXP_LIKE function. For example, some developer use the following to validate whether a string is a number but it only validates whether the first character is a number.
Indexes are separate data structures that provide alternate pathways to finding data. They can and do generally speed up the processing of queries and other DML commands, like the INSERT, UPDATE, REPLACE INTO, and DELETE statements. Indexes are also called fast access paths.
Have you ever wondered how to leverage substitution variables in anonymous block programs? There are several tricks that you can use beyond passing numeric and string values to local variable. The generic default appears to take a number unless you cast it as a string but that’s not really the whole story. The first two are standard examples of how to use numeric and string substitution values.
The following accept a numeric substitution value:
Using an Oracle object type’s instance in a query is a powerful capability. Unfortunately, Oracle’s SQL syntax doesn’t make it immediately obvious how to do it. Most get far enough to put it in a runtime view (a subquery in the FROM clause), but then they get errors like this:
Sometimes I give parts of a solution to increase the play time to solve a problem. I didn’t anticipate a problem when showing how to perform a sort operation with a CASE statement. It’s a sweet solution when you need to sort something differently than a traditional ascending or descending sort.
I gave my students this ORDER BY clause as an example:
This how you install SQL Developer on Mac OS Yosemite. The first thing you need to do is download and install Java 8, not Java 7 on your Mac OS Yosemite as suggested on some web sites. You can determine whether or not Java is installed by running the following command:
While working through getting my Mac OS X to work with X11, I stumbled on some interesting errors and misdirection solutions. Like most things, the solution was straightforward. Then, it struck me that I hadn’t installed it on my Fedora image. This blog post show you the errors I got the way to get it to work, and how to install X11 on Fedora.
The first step requires discovering the package. If you remember xclock or xeyes are X-Windows programs, it’s quite easy with this command (though it may take a moment or two to run):
Last week, I wrote about how to use bash arrays and the MySQL database to create unit and integration test scripts. While the MySQL example was nice for some users, there were some others who wanted me to show how to write bash shell scripts for Oracle unit and integration testing. That’s what this blog post does.
Student questions are always interesting! They get me to think and to write. The question this time is: “How do I write a Bash Shell script to process multiple MySQL script files?” This post builds the following model (courtesy of MySQL Workbench) by using a bash shell script and MySQL script files, but there’s a disclaimer on this post. It shows both insecure and secure approaches and you should avoid the insecure ones.
While I previously blogged about installing Netbeans 8, some of my students would prefer to use the Eclipse IDE. This post shows how to install and configure Eclipse IDE, include the mysql-connector-java.jar, and write Java to access the MySQL.
A reader posted A dynamic level limiting hierarchical query about Oracle’s hierarchical queries. They wanted to know how to capture only the hierarchy to the level where the first leaf node occurs. They gave me the following hierarchy map as an example:
Some of my students want to use the Fedora image that I built for my database classes in my Java software development life cycle course. As a result, they wanted a Java development environment installed. I examined JDeveloper 11g (220.127.116.11.0) and 12c (12.1.3) but resolved on the more generic Netbeans 8 (8.0.2) IDE.
This is the continuation of my efforts to stage an awesome Fedora developer’s instance. It shows you how to install Java 1.8 software development kit, which is nice to have. Though you can’t use Java 1.8 officially with Oracle SQL Developer 4.0.3 it is required for Oracle SQL Developer 4.1. Fortunately, the Oracle Product Manager, Jeff Smith has advised us that you can use Java 1.8 JDK with Oracle SQL Developer 4.0.3, and he’s written a comment to the blog post that it runs better with the Java 1.8 SDK.
Back in January 2014, I wrote a script to cleanup an Oracle student schema. It worked well until I started using APEX 4 in my student schema. You create the following 75 objects when you create an APEX 4 schema.
Somebody suggested that I try out thin, “A fast and very simple Ruby web server.” So, I thought it might be interesting to test, and a simplification over Rails to demonstrate an small Ruby MVC pattern.
Installing thin seemed straight forward as a gem installation, like
From time to time, folks ask questions about how to solve common problems in Linux or Unix. Today, the question is: “How do I find a list of files that contain a specific string?” There are two alternatives with the find command, and the following sample searches look for files that contain a sqlite3 string literal.
It turns out that configuring Perl wasn’t the last step for my student instance. It appears that I neglected to configure my student instance to support Java connectivity to MySQL. This post reviews the configuration of Java to run programs against MySQL. It also covers the new syntax on how you register a DriverManager, and avoid Java compilation errors with the older syntax.
Sometimes trying to keep a post short and to the point raises other questions. Clearly, my Python-MySQL Program post over the weekend did raise a question. They were extending the query example and encountered this error: