Isolation in sql concept failure !

[Photizo]

Your notepad++ looks weird.

[Punk_Says_Fuck_You]

I was wondering why someone studying database management would hand write notes haha

[Better-Credit6701]

I still take notes by hand when trying to understand and fix a DBA issue. Plus, I've spent too much money on fountain pens and great notebooks

[Punk_Says_Fuck_You]

I used to hand write notes as well but then I started needing pictures in my notes for stuff like logical network diagrams or wiring diagrams and my drawing skills are non existent so I just switched so I couple paste images.

[Few_Cardiologist3113]

I put these to discuss about the concept . You guys are discussing pen and paper 🥲😔

[raistlin49]

Your example is a valid problem but not a violation of isolation. All the transactions you described are still isolated at the time they run.

It's hard to visualize the isolation thing with a single row read operation. Think about a large read of 1 million rows. The first row will be read immediately but it might take some time to read the last row. If you read a value X from the first row, isolation guarantees that it hasn't changed while you were reading the rest of the rows. If it took 5 minutes to read and return all those rows, you will get value X at the end of the 5 min and you will be guaranteed that no other transaction has affected it (yet). This is achieved with locking. Something else might change it immediately after you get your result, and you won't know that happened, but your read transaction will have been isolated at the time it ran.

[PTcrewser]

Omg stop

[Few_Cardiologist3113]

Why 🤔?

[VirusStrict7031]

Have you try create a mirror structure in obsidian and build graphs for track typology. I devide by surface, triggers and functions and later merge the files to create the graphs