Sunday, March 30, 2014

Diving In

If you don't know, SourceForge hosts thousands of open source development projects.  So, I've thrown my hat into the ring to see if anyone wants a newbie Java developer with advanced database skills.  We will see if I get any takers.  To see my "Project Wanted" post, click here.

The problem I found when trying to get involved is that the number or projects is overwhelming and the descriptions of what is needed leave something to be desired.  I guess I expected the "Programmers Wanted" section to look more like the job postings you see on Monster.com or CareerBuilder.com.  Instead, they tended to be vague, "Looking for developers with experience in Java, MySQL, JSP."

Well, I did find one project that I might be a suitable match.  I've sent my request to the project admin.  Only time will tell if I found a niche.  In the meantime, I'm going back to working on my own project.

Saturday, March 22, 2014

MySQL for Excel Append Error (and a solution)

I use the MySQL for Excel add-in in order to move data between my MySQL database and an Excel workbook I depend on.  Recently, I encountered this error when I tried to append data to a table I had successfully used.  This is my experience and the solution I found.



The source data had nearly 2,000 rows and over 50 columns being appended.  Initially, I created the table using the MySQL for Excel Add-in, then tested it by performing a second append.  I moved to a different set of data and found that about half the columns did not exist in the second data set.  Since much of it was duplication or data validation, I decided to shorten the table by removing the unused columns.

Once the columns were removed, the error above appeared.  I dropped and recreated the table, stopped and started Excel, logged out of the connection and back in, but nothing corrected the problem.  I found the same problem asked on Stackoverflow, but there was no answer.  I couldn't find a reference to the problem anywhere else.

The next day, it occurred to me that the mapping stored within the add-in may be failing because it couldn't find the columns I had removed from the table and didn't know how to adapt.  Sure enough, I restored the dropped columns and the append worked exactly as expected.


Friday, March 21, 2014

Introduction

I have been writing code of one variety or another for the past 30+ years.  Ninety percent of my knowledge is self taught, often because I had a problem that had to be solved.

I would consider myself an expert when it comes to SQL based languages.  I started playing with DBase 3 in college and have progressed through MS Access and Excel to Oracle, SQL Server and MySQL.  There isn't much I can't make a relational database do and I know where the tricks and traps are in all of the products I listed.

My latest project involves creating a desktop task management application using Java and MySQL.  Other systems exist, but I have particular tastes and had been using a custom built MS Access application for several years.  But being tied to a licensed product has it's drawbacks, so I decided to start on an open-source based replacement.  Enter MySQL and the Netbeans IDE.

Since my skills are heavy on the database side, the data model is complete and robust.  Unfortunately, the Java side is progressing much more slowly.

Since nearly all my free coding time is spent on this application, the focus of most of my posts will be on the problems and solutions I've found.

I hope you check back often and comment.  I could certainly use the help.

One final note.  One of my favorite projects and my first professional "database" application was built using the mail merge functionality in WordPerfect 5.1.  I used it to manage the trouble tickets that my division handled.  The entire thing was stored on a 3.5HD floppy.  Although it was crude, it saved me time and the reports I created impressed my bosses at the time.