goto11

78 ms·

811.
by goto11 5y ago
SQL is often conflated with the relational model (hence the term NoSQL for non-relational databases), but the article is careful to explain that the relational model is great, but SQL is a clunky syntax/standard. Going to graph databas
812.
by goto11 5y ago
You can already do that by having circle and rectangle relations. Union types dos not give you any additional power compared to relations. Your proposal might be more convenient though than creating multiple relations, so we should look int
813.
by goto11 5y ago
SQL already have first class support for union types in the form of relations. Adding union-type columns would actually be second class compare to this. You would have to add special-case operators and it wouldn't give you more power c
814.
by goto11 5y ago
Couldn't you just as well conclude that lead-eating emperors lead an empire to expand and prosper for centuries?
815.
by goto11 5y ago
The article posit "erratic rulers" as a possible cause for the downfall of the Roman Empire. As examples of such erratic rules it mention Claudius, Caligula and Nero. The problem with this theory is that the fall (if we take 476 A
816.
by goto11 5y ago
YAGNI is is also postponing abstractions, flexibility and extension points until the application requires it. But for a library you need to design the abstractions up front because you don't know the requirements of the users, and it
817.
by goto11 5y ago
The number of notes is also historical tradition, e.g. pentatonic vs heptatonic.
818.
by goto11 5y ago
> if we have strong reasons to prefer a simple text file, then we should. But by default, we should go for sqlite or something bigger. That seems like the opposite of the YAGNI principle though.
819.
by goto11 5y ago
The calculator on Windows does persist a few settings, for example windows size and whether "scientific" or "standard" mode is selected. This could be saved in a config file or some other storage format. Windows has a si
820.
by goto11 5y ago
YAGNI only applies for a "top-level" applications. For libraries used by third parties (e.g. the standard library of a language) you want clients do be able to do things you haven't imagined, so different trade-off are in pla
821.
by goto11 5y ago
A bunch of different scales is used in different cultures and traditions around the world. The choice of a scale is an interesting combination of universal math and tradition. Scales are built from intervals which a are basic ratios - 1&#x2
822.
by goto11 5y ago
1NF is defined in terms of attribute domains on the logical model. It all comes down to if the value is atomic with regard to relational algebra. Can you project attributes or insert tuples in the value using the standard relational operato
823.
by goto11 5y ago
> 1NF is about eliminating nested relations. Absolutely agree, this is the definition of 1NF. So if you have a relation which has an attribute which has a domain which itself include relations - then you have a 1NF violation. "From
824.
by goto11 5y ago
Relations, attributes, and domains all exist on the logical level. The relational model deliberately does not say anything about the physical level. Domains are the data types of columns. If a column has the type VARCHAR, then the domain is
825.
by goto11 5y ago
This is what the article discuss. 1NF is about eliminating nested tables, which is not supported by SQL. Dumping a list of phone numbers into a string does not violate 1NF because a string is still just a single value from the perspective o
826.
by goto11 5y ago
Yep, following the idioms of a language is almost always better than trying to make it look like some other language, even if the emulated language is more fashionable.
827.
by goto11 5y ago
If you look at his drawings and sketches you can see he mastered realistic figure drawing and perspective pretty well. His weird perspectives and figures in the later paintings is clearly an artistic choice, not lack of basic drawing abilit
828.
by goto11 5y ago
> Surely "exactly one value" from the applicable domain of telephone numbers is a telephone number, not a comma-delimited list of telephone numbers. Yes certainly. But note that when we talk about comma-separated values, we are
829.
by goto11 5y ago
Wikipedia is imprecise in this passage. First normal form is defined in terms of domains , not values . Domains is basically the data type of a column. So the question is what the type of the column is. If the column type is string (or
830.
by goto11 5y ago
Note that the letter is probably not authentic, and does not reflect how an actual Sultan would describe himself.
831.
by goto11 5y ago
They don't claim an insulting letter never happened, just that the quoted text is not authentic.
832.
by goto11 5y ago
Note that the people in r/AskHistorians are actual historians, or people knowledgeable enough of the subject to source their claims.
833.
by goto11 5y ago
For historians it matter, which is why the discussion is on AskHistorians.
834.
by goto11 5y ago
It is AskHistorians, a very strongly moderated sub-reddit where comments get deleted if they can't show valid sources. The discussion is much higher level than here on HN.
835.
by goto11 5y ago
> The normal forms are guidelines for using relational databases as intended, to minimize these problems, when it might matter. I think the discussion comes down to different ideas about what "normal form" means. Is it some sem
836.
by goto11 5y ago
That is not what synthetic key means. A synthetic key is a key which does not carry any information, like an auto-incremented integer. A date is a natural key, regardless of the underlying representation.
837.
by goto11 5y ago
They should not be allowed according to C.F.Date, but this is quite a controversial opinion. E.F.Codd who invented the relational model thinks nulls are fine.
838.
by goto11 5y ago
But isn't Codd's relational algebra based on 1NF relations? The point of 1NF is (among other things) to make the algebra simpler because you don't need to handle nested relations. A database built on non-1NF relations would b
839.
by goto11 5y ago
Can you elaborate on why you think that? 1NF does not say anything about physical representation, it only talks about the logical model.
840.
by goto11 5y ago
1NF as defined by E.F.Codd literally does not allow relation-values attributes.

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