I sail the high seas of the Lemmyverse, posting snarky + Lefty comments

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Joined 3 years ago
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Cake day: May 7th, 2023

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  • Hard to say right now. The article suggests that the banks are just trying to free up cash on their balance sheets. However, this could instead be an indication that they are looking for a “bigger fool” to take the losses. I personally think the bottom won’t fall out of Xitter until the tesla share price crashes. Elon bought some time with credulous fools with the ridiculous cybercab demo, but that can’t last forever. At that point I think the only question is whether SpaceX gets pulled down with all the rest of the musk ventures






  • ELI5: a database is the “memory” of a program.

    Every piece of data that any software uses almost certainly comes from and goes to multiple databases.

    Once the data is stored, you can execute “queries” to have powerful access to update many records at a time, read particular records based on their relationship to other records, and so much more.

    Your bank balances, your purchase history, your emails, every part of your digital life is almost certainly spread across a constellation of databases.

    Bonus Fediverse content:

    Lemmy itself uses the Postgres database extensively. Posts, users, comments, votes and more are all individually stored in the database.

    Mastodon also uses Postgres. If a post goes up on Lemmy, and a Mastodon server is federated with it, the Lemmy server will send out a HTTP request to the Mastodon server containing the contents of the post. The Mastodon server will use this information to write its own record of the post in its own database.

    Regarding your question about VMs: You can run a database inside a VM, or give the VM access to an outside database via queries, or both! You might run SQLlite (a small and excellent embedded database) on the VM to track its local state, while also running queries against a large postgres database to synchronize with other services in the cluster.



  • I did a little research and the answer is pretty interesting!

    Originally, chemists assigned hydrogen a mass number of 1, and used that assumption to derive the masses of the other elements. Today we definine “1” as being 1/12 of the weight of Carbon-12 (which is very close to the average weight of hydrogen we use today)

    As to the relative frequencies, they can be different at different points on earth, this Chemistry SE answer goes into a lot more detail.

    If you have never done “stoichiometry” before it may not be obvious but the periodic table average weights are essential for going from “I have x grams of substance” to “I have x number of atoms/molecules of substance” and from there you can use the equation of your target reaction to precisely predict the outcome of a chemical process. If you were doing very high precision chemistry, the differences in isotopic ratio in your sample vs the standard values could introduce an error but I would guess most of the time it is insignificant.