This is very similar to my server in the story below.

TSQL Tuesday info.

TSQL Tuesday is a blogging event that happens on the 2nd Tuesday of the month. This week’s host is Louis Davidson (https://drsql.link/2026/01/13/t-sql-tuesday-194-invitation-learning-from-mistakes/)

You can find all the key rules and information on hosting if you would like to host at this link. https://tsqltuesday.com/

The Request. 

I haven’t participated in a #TSQL Tuesday in quite some time.  I saw this topic and said, “That’s perfect!”  I love talking about Failure and mistakes!  I have a whole presentation about it, and I’m hoping to make a series of blog posts about it very soon.   

You do not learn from success in life; you learn from failure.  I hope you are making lots of mistakes so that you can learn! 

“This month, I am asking you to share about a mistake you made that touches on data in some way. Whatever the mistake was, maybe when you were a complete newbie, maybe just last week.”

I have lots to choose from, but I have been very nostalgic as of late, so I’ll go to one of my very first mistakes as a DBA. 

Some of you won’t even be able to go back this far in technology, but some of you will appreciate this.  It was Mid 1999. I was just learning about Databases and had only recently inherited a Sybase SQL Anywhere DB.  I had no formal training in SQL and just a general understanding of what the Database was and what it did.  I was a customer support manager and needed to figure out this new DB that we were using.  It quickly became evident that I preferred working on the DB items to the manager items.  My passion at the time was the technical side of things.  

It started with a simple request: The DB had a front-end called HEAT (later Goldmine CRM).  This system allowed the creation of simple forms and the entry of data about support tickets and customers.  We needed a backend process that would update the phone number whenever another field was updated.  I had just read something about Triggers… yeah, some of you know where this is going.  

So I wrote up a Trigger that updates the phone number field whenever another field is updated.  Pretty simple…..Unfortunately, the trigger updated every phone number in the table every time an agent updated a field in the system. I didn’t understand that each update was row-level, but the query was acting on the whole table, and I didn’t specify that it should only update the record that was changed.  As people started using the system, it would wait about a minute each time to update all the other records. Luckily, the data was still correct since it was just updating the same row, but it was using all the system resources.  Since this was the late 90’s, we didn’t have high-powered servers. The DB didn’t stand a chance of staying up and running correctly.  It took most of the afternoon for us to bring the server down, start it back up, and remove the trigger.  We weren’t sure what the issue was at first, but then I remembered the change I made. 

Luckily, it was a small company, and they were pretty used to the system going down throughout the day.  Uptime wasn’t as big a thing back then as it is now.  I learned some great lessons on this day, and they have continued to shape me as a DBA.   

Lessons Learned 

1. Test everything!  I did not have a testing environment for this system. 
2. Respect all Triggers. I’ve seen tons of triggers since this first issue, and I’ve questioned every one of them to understand whether they are fully needed and how they are used.  They are very powerful and very dangerous. 
3. Enjoy the early days and the small companies. Suppose you find yourself in a DBA position in a small company and are just learning new things.  Enjoy that time! Use that time to really learn about some of these things that can go wrong.  I learned a ton of important lessons at this company. 
4. Ask questions and seek out others. I was the lone DBA at the time and had no one else to bounce ideas off.  I didn’t find community till years later, and I’m sure it would have helped if I had a community back then.