As "deadlines" approach, feature sets get cut down, then there are delays, and finally a feasible feature set is delivered some time after the deadline.
The only deadlines that can be met are those of tasks which have already been done but not announced.
This is of course Hofstadter's law.
About 50k subscribers on 2021, which feels way too little for the video quality and quantity.
Ciro Santilli believes that this channel will go very far, certainly achieving 1M subscribers in they keep it for one or two more years. Update: it didn't, as of 2024, shame.
They are Utah-based, and they do many many amazing weekend trips. They mostly drive from home to some trailhead, and then climb up and down it the entire day.
No technical rock climbing, only bouldering, but they still manage to reach many amazing places, and there is a level of danger in many of their ascents.
These appear to be benchmarks that don't involve running anything concretely, just compiling and likely then counting gates:
Answers suggest hat you basically pick a random large odd number, and add 2 to it until your selected primality test passes.
The prime number theorem tells us that the probability that a number between 1 and is a prime number is .
Or: how to learn X.
That is the wrong question.
Then, once you decide to try one, if that involves programming, only then learn to program to achieve that goal. And don't stop learning what's needed until you either get the thing done, or decide that it is actually not a good idea, or not possible, or that there is something else more important to be done first.
But if doesn't involve programming, then don't learn to program, and learn whatever you actually need to reach that goal instead.
Having that goal is the only way to be motivated to do something.
This is the essence of backward design.
Another very important point to keep in mind is: Section "When in doubt, choose the course that has the most experimental work".
How to decide if an ORM is decent? Just try to replicate every SQL query from nodejs/sequelize/raw/many_to_many.js on PostgreSQL and SQLite.
There is only a very finite number of possible reasonable queries on a two table many to many relationship with a join table. A decent ORM has to be able to do them all.
If it can do all those queries, then the ORM can actually do a good subset of SQL and is decent. If not, it can't, and this will make you suffer. E.g. Sequelize v5 is such an ORM that makes you suffer.
The next thing to check are transactions.
Basically, all of those come up if you try to implement a blog hello world world such as gothinkster/realworld correctly, i.e. without unnecessary inefficiencies due to your ORM on top of underlying SQL, and dealing with concurrency.
Funding:
- 2023: 1.1m pounds www.uktech.news/deep-tech/lumai-grant-20230215
An example where
SELECT FOR UPDATE is a good solution to an use case can be seen at: nodejs/sequelize/raw/parallel_select_and_update.js.SELECT FOR UPDATE vs/together with the SQL transaction isolation level is commented at: stackoverflow.com/questions/10935850/when-to-use-select-for-update.- foreign keys are capitalized:
- you must give
foreignKeywhen using aliases, otherwise it fails subtely. That would be derived automatically. - stackoverflow.com/questions/41502699/return-flat-object-from-sequelize-with-association can't auto-flatten to reuse the database's
ORDER limitandoffsetdon't work withoutsubQuery: falsewhen doing includes! It is just too buggy. Examples of this can be found e.g. under nodejs/sequelize/many_to_many_same_model.js.- stackoverflow.com/questions/34059081/how-do-i-reference-an-association-when-creating-a-row-in-sequelize-without-assum hard to not duplicate foreign keys values everywhere
- stack traces permanently broken or requiring non-obvious configs:
- does not automatically update fields on hooks: github.com/sequelize/sequelize/issues/8586#issuecomment-422877555
- cannot change columns when other columns have constraints due to the backup table?
- you have to use
.get()forattributealiased fields, why? stackoverflow.com/questions/32649218/how-do-i-select-a-column-using-an-alias/69890944#69890944 .idgets added toSELECTno matter what, breakingGROUP BYunless you do horrible workarounds:- no simple built-in mechanism for transaction retries: Sequelize transaction retries
- impossible to do subqueries in general. Docs just tell you to use literals. This in particular prevents single query deletes with join as done at nodejs/sequelize/raw/many_to_many.js:Also, you can't get query strings either: github.com/sequelize/sequelize/issues/2325
- sequelize.org/master/manual/sub-queries.html: the docs actually just tell you to use literals, lol
- stackoverflow.com/questions/45354001/nodejs-sequelize-delete-with-nested-select-query
- migrations. Generally speaking, anything but the simplest migrations are exceedingly hard to get right, as you have to go very low level when doing migrations. Syntax can be very different from regular DB operations.
- no way to do (non-raw) queries during migrations, e.g. to update fields based on other fields in a complex way?
- github.com/sequelize/cli/issues/862
- stackoverflow.com/questions/18742962/add-data-in-sequelize-migration-script
- stackoverflow.com/questions/38671483/sequelize-migration-update-model-after-updating-column-attributes
- stackoverflow.com/questions/38998397/can-i-use-sequelize-models-in-migration-scripts
- stackoverflow.com/questions/45286429/custom-query-on-sequelize-seeder
queryInterface.sequelize.modelscontains onlySequelizeMeta. Not sure why they have this limitation. - stackoverflow.com/questions/56043246/node-js-sequelize-no-primary-keys-when-migrating/56046101#56046101
- SQLite
changeColumnmigrations do on delete cascades of other tables. SQLite does not have change column statements, so they have to drop and recreate tables, but they don't temporarily remove cascades, so you lose data: stackoverflow.com/questions/62667269/sequelize-js-how-do-we-change-column-type-in-migration/70486686#70486686 - associations require full explicit index construction: stackoverflow.com/questions/39651853/how-to-create-join-table-with-foreign-keys-with-sequelize-or-sequelize-cli
- ability to iterate over a large result without blowing up memory and without using limit + offset (which is inneficient e.g. when looping over recursive queries). This is also known as cursor or streaming interfaces:E.g. the Python SQLite interface supports this just fine: stackoverflow.com/questions/29582736/python3-is-there-a-way-to-iterate-row-by-row-over-a-very-large-sqlite-table-wi
- stack overflow
- stackoverflow.com/questions/28787889/how-can-i-set-up-sequelize-js-to-stream-data-instead-of-a-promise-callback
- stackoverflow.com/questions/43964067/how-to-implement-cursor-pagination-using-sequelize
- stackoverflow.com/questions/57164242/perform-sequelize-findall-in-a-huge-array
- stackoverflow.com/questions/55191891/how-to-loop-through-result-in-sequelize generic loop
- issue tracker
- stack overflow
- empty
attributes: []breaks some nested queries: github.com/sequelize/sequelize/issues/16436 - does not expose a iteration API that supports large arrays?E.g. Python SQLite does: stackoverflow.com/questions/29582736/python3-is-there-a-way-to-iterate-row-by-row-over-a-very-large-sqlite-table-wi
Our WIP script: wikipedia/import-categories.sh.
Related:
- opendata.stackexchange.com/questions/1533/download-wikipedia-articles-from-a-specific-category
- webapps.stackexchange.com/questions/16359/is-there-a-way-to-download-a-list-of-all-wikipedia-categories/172480#172480
- stackoverflow.com/questions/40119322/how-to-download-all-pages-inside-a-category-in-wikipedia
- category tree on Stack Overflow
- stackoverflow.com/questions/17432254/wikipedia-category-hierarchy-from-dumps/77313490#77313490 Canon but no good answers.
- stackoverflow.com/questions/12227134/how-to-fetch-category-tree-of-wiki
- stackoverflow.com/questions/21782410/finding-subcategories-of-a-wikipedia-category-using-category-and-categorylinks-t. Actually explains it: stackoverflow.com/questions/21782410/finding-subcategories-of-a-wikipedia-category-using-category-and-categorylinks-t/21798259#21798259
- stackoverflow.com/questions/27279649/how-to-build-wikipedia-category-hierarchy
- mdkzaman.com/knowledge-graph-from-wikipedia-category-hierarchy/
Consider:
Let's observe them in MySQL:outputs:
mysql enwiki -e "select page_id, page_namespace, page_title, page_is_redirect from page where page_namespace in (0, 14) and page_title in ('Computer_storage_devices', 'Computer_data_storage')"+----------+----------------+--------------------------+------------------+
| page_id | page_namespace | page_title | page_is_redirect |
+----------+----------------+--------------------------+------------------+
| 5300 | 0 | Computer_data_storage | 0 |
| 42371130 | 0 | Computer_storage_devices | 1 |
| 711721 | 14 | Computer_data_storage | 0 |
| 895945 | 14 | Computer_storage_devices | 0 |
+----------+----------------+--------------------------+------------------+mysql enwiki -e "select cl_from, cl_to from categorylinks where cl_from in (5300, 711721, 895945, 42371130)"+----------+-----------------------------------------------------------------------+
| cl_from | cl_to |
+----------+-----------------------------------------------------------------------+
| 5300 | All_articles_containing_potentially_dated_statements |
| 5300 | Articles_containing_potentially_dated_statements_from_2009 |
| 5300 | Articles_containing_potentially_dated_statements_from_2011 |
| 5300 | Articles_with_GND_identifiers |
| 5300 | Articles_with_NKC_identifiers |
| 5300 | Articles_with_short_description |
| 5300 | Computer_architecture |
| 5300 | Computer_data_storage |
| 5300 | Short_description_matches_Wikidata |
| 5300 | Use_dmy_dates_from_June_2020 |
| 5300 | Wikipedia_articles_incorporating_text_from_the_Federal_Standard_1037C |
| 711721 | Computer_architecture |
| 711721 | Computer_data |
| 711721 | Computer_hardware_by_type |
| 711721 | Data_storage |
| 895945 | Computer_data_storage |
| 895945 | Computer_peripherals |
| 895945 | Recording_devices |
| 42371130 | Redirects_from_alternative_names |
+----------+-----------------------------------------------------------------------+So we see that
cl_from encodes the parent categories:- parent categories of categories:
- en.wikipedia.org/wiki/Category:Computer_data_storage, which has ID
711721, has parent categories: "Computer hardware by type", "Computer data", "Data storage", "Computer architecture". This matches exactly on the database. These are all encoded on the source code of the page:{{DEFAULTSORT:Storage}} [[Category:Computer hardware by type]] [[Category:Computer data|Storage]] [[Category:Data storage|Computer]] [[Category:Computer architecture]] - en.wikipedia.org/wiki/Category:Computer_storage_devices has parent categories: "Computer data storage", "Recording devices", "Computer peripherals". This matches exactly on the database.
- en.wikipedia.org/wiki/Category:Computer_data_storage, which has ID
- parent categories of pages:
- en.wikipedia.org/wiki/Computer_storage_devices whish is a redirect gets the magic category "Redirects_from_alternative_names", a humongous placeholder with many thousands of pages: en.wikipedia.org/wiki/Category:Redirects_from_alternative_names
- en.wikipedia.org/wiki/Computer_data_storage shows only two categories onthe web UI: "Computer data storage" and "Computer architecture". Both of these are present on the database and at the end of the source code:The others appear to be more magic. Two of them we can guess from the templates:
{{DEFAULTSORT:Computer Data Storage}} [[Category:Computer data storage| ]] [[Category:Computer architecture]]are likely{{short description|Storage of digital data readable by computers}} {{Use dmy dates|date=June 2020}}Use_dmy_dates_from_June_2020andArticles_with_short_descriptionbut the rest is more magic and not necessarily present in-source.
So to find all articls and categories under a given category title, say en.wikipedia.org/wiki/Category:Mathematics we can run:
mariadb enwiki -e "select cl_from, cl_to, page_namespace, page_title from categorylinks inner join page on page_namespace in (0, 14) and cl_from = page_id and cl_to = 'Mathematics'"TODO: it would be cool to have something like bitcoinstrings.com but including the actual transactions:
Local methods:
- Bitcoin Inscription Indexer
- bitcoin.stackexchange.com/questions/30295/how-can-i-search-for-transaction-text-on-the-blockchain
- bitcoin.stackexchange.com/questions/22500/is-there-a-lightweight-blockchain-parser-library-server/101472#101472
- github.com/alecalve/python-bitcoin-blockchain-parser
- bitcoin.stackexchange.com/questions/84266/wondering-how-to-use-bitcoin-parser
- github.com/bitcoinprivacy/Bitcoin-Graph-Explorer stores the blockchain in a database, and should allow more intelligent querying.
Further bibliography:
- bitcoin.stackexchange.com/questions/799/can-i-download-the-whole-block-chain-from-somewhere
- bitcoin.stackexchange.com/questions/68925/how-can-data-be-accessed-searched-for-in-a-blockchain
- bitcoin.stackexchange.com/questions/55188/download-single-and-specific-block-for-study-purposes
- www.fiverr.com/usefulshine/embed-your-logo-or-brand-art-on-blockchain user usefulshine from India embeds ASCII art for you into the blockchain starting at 260 dollars! XD
Ciro Santilli had to see this in a few separate places, until he underestood: that little pictur emust be a thing! Examples:
- mojim watermarks: mojim.com/twy105509x7x2.htm
- some Japanese website: kotobank.jp/word/%E5%A4%A7%E7%96%91-556655
This is Ciro Santilli's ideal university system. It is a system that actually lives up to the name "Open University":
- no enrolment, no prerequisites. Exam as a service examination style, likely free to anyone who wants to take them, only to determine:
- who gets to use physical facilities, notably laboratories
- which students do you want to pick as apprentices/workers/PhDs
- no tuition fees: free gifted education
- school must offer free accommodation for students
- force teachers to publish their teaching material with an open license
- how to teach
Related:
- reallyopenuniversity.wordpress.com/what-is-the-rou/
Apparently Leeds based. Focused only on student fees seemingly, not how to solve it with tech/efficiency:
So far as of the early 2020's, the university that comes closest to some but not all of these principles is the University of the People. It's sad that it's such a crappy unknown thing, but it is what it is.
Once you have crated something awesome, you have to advertise it, otherwise no one will ever find it.
This means:
- Then ask them if they want to talk about anything.
- whenever someone asks as question on an online forum, answer it, and link to the section of your material that also answers that question.The material will answer many of their future questions.
Eventually, people will find you on the front page of Google searches, and then you will know that you've truly made something useful.
Text materials are generally superior to video because they:
Only produce video material if:
- it shows an experiment, physical technique, natural phenomena or location that is of interest. See also: Section "Videos of all key physics experiments"
- it gives fundamental geometric insight on the subject
- you are filming a human transmitting their passion about the subject, and the speaker is amazing, and does not speak for too long
Messaging software that force you to have a mobile phone Updated 2025-06-17 +Created 1970-01-01
Chat programs that don't have a proper web-only operation and force you to have a mobile phone, e.g. WhatsApp.
Heck, even Signal, which is supposed to be super secure and good for your privacy, forces you to disclose your freaking cell phone to all contacts! lifehacker.com/how-to-use-signal-without-revealing-your-private-phone-1818996580
There are unlisted articles, also show them or only show them.