Exploring Business Central Custom Table Indexes

by Steve Endow

In my last post, I poked around in SQL to see what custom fields looked like in the database for a Business Central table extension.

While looking into fields, I happened to notice the table index that is automatically created for the table extension.

Automatic Table Extension Index

If we look at this index, we see it is a Clustered Unique index for the "No_" field only.

Default Clustered Index on Table Extension

Why is this default index created automatically?  This Table Keys docs page briefly mentions the default Clustered Index on table extensions.

Business Central Custom Fields and Default Field Values

by Steve Endow

When you add new fields to an existing Business Central table, what happens?  

What does Business Central do in the database?  How does Business Central handle default field values?  

I didn't know the answers to these questions, so I decided to do a few tests.  For fun, obvs!

To keep things simple, I created a Table Extension object in AL.  I assume this applies to creating custom tables and adding fields to an existing custom table, but I figured a Table Extension would be simpler and easier to test with, and I learned a few more things about table extensions in the process.

Simple Customer Table Extension 

Mitigating WiFi deauth attack with Protected Management Frames in Unifi (aka 802.11w Management Frame Protection MFP)

by Steve Endow

Note:  In case the title didn't make it obvious, this post has nothing to do with Business Central.  I wanted to document my learning because I found very little reliable or current information on mitigating WiFi deauth attacks, as of May 2022.  If I got anything wrong or if you find a good resource covering this topic, please post a comment and let me know.

When I'm not trying to learn Business Central, I like to learn about computer security.  I'm not a computer security expert by any means, just someone who finds it interesting as a side hobby.

While learning about password cracking several months ago, I learned about Kali Linux, an amazing distribution that includes lots of different computer and network security tools pre-installed.

In order to learn how to use Kali Linux and the security tools it includes, I decided to try to learn how to crack my WiFi password.  It seemed like a fun exercise, and it was.  But it just happened to teach me something entirely unexpected.

While following the instructions in this "Hacking Wi-Fi" guide (which had some minor omissions--I recommend using this version instead), I was quite surprised when I read this step:

"...disconnect the clients connected to the target network..."

Wait, what?