#constraint — Public Fediverse posts

[Перевод] Ограничения целостности с отложенной проверкой в PostgreSQL

По умолчанию, ограничения целостности в PostgreSQL проверяются немедленно, сразу после обновления каждой строки, что может быть неоднозначным при обновлении нескольких строк. Рассмотрим пример с одной таблицей, имеющей один столбец с уникальным ограничением (и индексом):

https://habr.com/ru/companies/tantor/articles/1055860/

#postgres #postgresql #constraint #unique

Flood Vulnerability And Load Capacity Assessment Of Historic Masonry Arch Bridges In Ireland Under Changing Climates
--
https://doi.org/10.1016/j.eve.2026.100153 <-- shared paper
--
H/T @Upaka Rathnayake
“HIGHLIGHTS:
• Field surveys and flood modelling were used to evaluate the resilience of eight historic masonry arch bridges in County Offaly, Ireland, under projected fluvial flooding conditions.
• Results indicate that increased flood levels and hydraulic forces can significantly reduce bridge load-carrying capacity, with potential reductions of up to 40% due to buoyancy effects during extreme flood events.
• The study demonstrates a clear relationship between flood exposure and structural deterioration, emphasizing the need for structural health monitoring, maintenance strategies, and climate-resilient infrastructure management…
ABSTRACT: Masonry bridges, predominantly constructed from stone or brick, were a common feature of bridge engineering during the 18th and 19th centuries. However, these historic bridges are still in use today, but they are at risk due to various extreme climate conditions. Thus, these bridges are vulnerable to damage and needy for investigation. This paper offers an in-depth analysis of the projected impacts of fluvial flooding stemming from climate change on a number of masonry arch bridge structures located in county Offaly, Ireland. It evaluates bridge resilience by examining estimated flood levels alongside the overall condition of the structures. These assessments play a crucial role in determining the load-bearing capacity of the bridges and whether adjustment factors should be implemented. Particularly for bridges situated on primary and secondary roads with consistent heavy goods vehicle (HGV) traffic, the potential decrease in load-bearing capabilities warrants significant consideration. This study highlights concerns regarding the resilience of these historic structures and presents a valid argument regarding their suitability for contemporary environmental conditions and present-day activities…”
#bridge #resilience #climatechange #impacts #loadcarrying #capacity #masonry #archbridges #fluvial #flood #flooding #Ireland #casestudies #transportation #bridges #historicbridges #history #survey #model #modeling #floodmodeling #CountyOffaly #ContaeUíbhFhailí #hydraulics #engineering #chokepoint #constraint #constriction #hydraulicforce #bridgeload #carryingcapacity #buoyancyeffects #damage #structuraldeterioration #structuralhealth #monitoring #maintenance #planning #policy #climateresilience #infrastructure #management #water #hydrography

I crashed a thread and ran off on this tangent to compare my Architecture of Encounter.

https://philosophics.blog/2026/03/27/plural-worlds-or-plural-mediations-goodman-meets-meow/?utm_source=masto&utm_medium=social

I prompted ChatGPT to do the heavy lifting.

#mediation #philosophy #ontology #epistemology #worldbuilding #blog #podcast #constraint #pluralism #metaphysics #grammar #systems #objectivity

What if the biggest trick language played on you is convincing you that the world is made of things?
https://www.youtube.com/watch?v=oOQD2n6cL-4
#philosophy #language #psychology #cognition #books #ontology #consciousness #minds #mediation #architecture #history #paradox #constraint #grammar #self #identity #video #youtube #meow #heuristics #reality

Why is the expectation of Truth so far-fetched? 🧐
https://philosophics.blog/2026/03/16/truth-subjectivity-and-constraint/?utm_source=masto&utm_medium=social
#philosophy #ontology #epistemology #truth #charts #blog #podcast #constraint #mediation #reality #language #science #infographic

We've seen incredible creativity born from constraints that seemed limiting initially. When you can't buy the solution, you must invent it instead.
Save this perspective for when budget limitations feel restrictive. Constraints often spark better solutions than unlimited resources.
What limitation forced you to find a creative solution? Sometimes barriers become unexpected breakthroughs.

#motorcycle #creative #innovation #solution #constraint

🎥 👉 @white_fortyeight_48

A quotation from Euripides

MENELAUS:        But so it has to be.
   For the saying is not mine, but it was wisely said,
   that nothing has more strength than dire necessity.
 
[ΜΕΝΕΛΈΩΣ:        ἀλλ᾽ ἀναγκαίως ἔχει.
   λόγος γάρ ἐστιν οὐκ ἐμός, σοφὸν δ᾽ ἔπος,
   δεινῆς ἀνάγκης οὐδὲν ἰσχύειν πλέον.]

Euripides (485?-406? BC) Greek tragic dramatist
Helen [Ἑλένη], l. 512ff (412 BC) [tr. Lattimore (1956)]

Sourcing, notes, other translations: wist.info/euripides/78063/

#quote #quotes #quotation #qotd #euripides #helen #compulsion #constraint #fate #necessity #needful #requirement

Gecode is an open source C++ toolkit for developing constraint-based systems

https://www.gecode.org/

#HackerNews #Gecode #C++ #toolkit #open #source #constraint #programming #system

A quotation from Euripides

HECUBA:   Then no man on earth is truly free,
   All are slaves of money or necessity.
   Public opinion or fear of prosecution
   forces each one, against his conscience,
   to conform.
 
ἙΚΆΒΗ:                                        [φεῦ.
   οὐκ ἔστι θνητῶν ὅστις ἔστ’ ἐλεύθερος·
   ἢ χρημάτων γὰρ δοῦλός ἐστιν ἢ τύχης
   ἢ πλῆθος αὐτὸν πόλεος ἢ νόμων γραφαὶ
   εἴργουσι χρῆσθαι μὴ κατὰ γνώμην τρόποις.]

Euripides (485?-406? BC) Greek tragic dramatist
Hecuba [Hekabe; Ἑκάβη], l. 864ff (c. 424 BC) [tr. Arrowsmith (1958)]

Sourcing, notes, other translations: wist.info/euripides/6979/

#quote #quotes #quotation #qotd #restraint #wealth #freewill #conformity #constraint #desire #fortune #freedom #inclination #judgment #law #luck #mob #money #popularopinion #resources

Валидация сложных форм с помощью Constraint Validation API

DOM предоставляет API для валидации пользовательского ввода. Вообще говоря, мы им пользуемся часто, например:

https://habr.com/ru/articles/906534/

#validation #constraint #forms

Аномалии конкурентного доступа

В распределённых базах данных YDB, CockroachDB по умолчанию используется уровень изоляции SERIALIZABLE. В PostgreSQL, Oracle Database, MySQL по умолчанию используется READ COMMITED. В стандарте SQL указаны только три аномалии. В статье приводится пример аномалии потерянного обновления в задаче "списания средств" и рассматривается, почему уровень READ COMMITED и ограничения целостности достаточны для решения задачи. Если с данными (строками таблиц) работает одна сессия в базе данных, то разницы между уровнями изоляции транзакций нет, так как нет транзакций, от которых нужно изолироваться. Если есть несколько транзакций, которые пересекаются во времени, то нужно обращать внимание на то, что параллельно с теми же данными работают другие транзакции. Другими словами, учитывать особенности (феномены, аномалии) "конкурентного доступа".

https://habr.com/ru/articles/894984/

#postgresql #sql #lost_update #изоляция_транзакций #constraint

Readings shared March 15, 2025. https://jaalonso.github.io/vestigium/posts/2025/03/15-readings_shared_03-15-25 #ACL2 #AI #CHR #Constraint #Constraints #Emacs #FormalVerification #FunctionalProgramming #Haskell #ITP #IsabelleHOL #Logic #LogicProgramming #MachineLearning #Math #NLP #Prolog

Principles of rule-based programming. ~ Thom Frühwirth. https://books.google.com/books/?id=ciVOEQAAQBAJ #CHR #Constraint #LogicProgramming

Clang Static Analyzer and the Z3 constraint solver
https://www.cambus.net/clang-static-analyzer-and-the-z3-constraint-solver/
#ycombinator #llvm #clang #scan_build #static #analysis #constraint #solver #cambus_net

'Homeomorphic Projection to Ensure Neural-Network Solution Feasibility for Constrained Optimization', by Enming Liang, Minghua Chen, Steven H. Low.

http://jmlr.org/papers/v25/23-1577.html

#optimization #constraint #constraints

What will happen if #Trump becomes #POTUS again:

1) End of #Democracy > #Autocracy (will last decades)
2) Corrupted #Judiciary/farce #elections.
3) End of World US power (which exists thanks to Alliances... which will cease).
3) End of 'dollar' as the world's primary #currency
4) Without alliances/without 'dollar' there will be an inevitable #economic #constraint
5) few rich ... many poor
6) end of 'workers' rights'
7) end of citizens' rights/Social medic supports
8) Police state.
...
enjoy

Constraints and Indications • 2
• https://inquiryintoinquiry.com/2024/07/04/constraints-and-indications-2-a/

Coping with collaboration, communication, context, integration, interoperability, perspective, purpose, and the reality of the information dimension demands a transition from conceptual environments bounded by dyadic relations to those informed by triadic relations, especially the variety of triadic sign relations employed by pragmatic semiotics.

Along the lines of my first post on this topic I am presently concerned with the logical and mathematical requirements of dealing with constraints but when it comes to the constraints involved in communicating across cultural and disciplinary barriers I could recommend a paper Susan Awbrey and I wrote for a conference devoted to those very issues.

Conference Presentation —

Awbrey, S.M., and Awbrey, J.L. (1999), “Organizations of Learning or Learning Organizations : The Challenge of Creating Integrative Universities for the Next Century”, Second International Conference of the Journal ‘Organization’, Re‑Organizing Knowledge, Trans‑Forming Institutions : Knowing, Knowledge, and the University in the 21st Century, University of Massachusetts, Amherst, MA.
• https://cspeirce.com/menu/library/aboutcsp/awbrey/integrat.htm

Published Paper —

Awbrey, S.M., and Awbrey, J.L. (2001), “Conceptual Barriers to Creating Integrative Universities”, Organization : The Interdisciplinary Journal of Organization, Theory, and Society 8(2), Sage Publications, London, UK, 269–284.
• https://journals.sagepub.com/doi/abs/10.1177/1350508401082013
• https://www.academia.edu/1266492/Conceptual_Barriers_to_Creating_Integrative_Universities

#Peirce #Logic #Semiotics #Indication #Inference #Information #Inquiry
#Ashby #Cybernetics #Constraint #Control #Regulation #RequisiteVariety
#AdaptiveSystems #IntelligentSystems #InquiryDrivenSystems #Pragmatics

Constraints and Indications • 1.2
• https://inquiryintoinquiry.com/2024/07/02/constraints-and-indications-1-a/

Re: Peirce List • Kaina Stoicheia and the Symbol Grounding Problem
• https://web.archive.org/web/20121231182129/http://comments.gmane.org/gmane.science.philosophy.peirce/9165

Reference —

• Ashby, W.R. (1956), Introduction to Cybernetics, Methuen, London, UK.

Resources —

Survey of Cybernetics
• https://inquiryintoinquiry.com/2024/01/25/survey-of-cybernetics-4/

Survey of Inquiry Driven Systems
• https://inquiryintoinquiry.com/2024/02/28/survey-of-inquiry-driven-systems-6/

Survey of Pragmatic Semiotic Information
• https://inquiryintoinquiry.com/2024/03/01/survey-of-pragmatic-semiotic-information-8/

#Peirce #Ashby #Cybernetics #InquiryDrivenSystems #PragmaticSemioticInformation
#Constraint #ControlSystems #Indication #Information #Inquiry #IntelligentSystems
#AdaptiveSystems #ErrorControlledRegulation #Feedback #SystemsTheory #Uncertainty
#Determination #Intentionality #Learning #Reasoning #SemioticInformation #Semiotics

🍾🍾There's a new #OCL interpreter in town!🍾🍾

With it, you'll be able to evaluate OCL expressions over a system snapshot 🤯🤯

📖 https://modeling-languages.com/ocl-interpreter/
⚙️ https://github.com/BESSER-PEARL/BOCL-Interpreter

#uml #lowcode #validation #verification #object #constraint #language

@uh @UlrikeHahn

I will focus here on "context" as more than the "space and time" in which something is observed to be/happen. I would emphasize that this sense of "context" is always _relational_ and is always plays some active role in shaping/constraining the perceived object system.

You may notice my use of words such as "observed" and "perceived". I may be taking this notion further than Juarrero, but I have long thought that _any_ meaningful description of a system is incomplete without including the context of the _observer_. (Often the observer goes without saying, but is always there.)

I am reminded of my high school physics class back in the 1970s, where I baffled and frustrated the instructor by my insistent questions asking for clarification of his definition of "entropy" as disorder. I kept trying to get him to see that the state of disorder must (it seems to me) be relative to the state of some observer. He never got it. I gave up and answered his test question about whether a scrambled egg has more entropy than a pristine egg in the shell, neglecting that the state of scrambledness may have been precisely the outcome for which work was done, to constrain the outcome.

Still bothers me... I'll sit down now and behave.

#entropy, #context, #constraint #JuarreroBook

So I have a new chapbook in the world!

A personal work of found poetry, 'In The Margins. . .' follows the loose narrative of a youth breaking free of their petit bourgeois upbringing, the consequent love, and ego-death.

Only $5!!! click the link!

#poetry #poem #smallPress #experimentalPoetry #foundPoetry #constraint #lyricPoetry
https://abovegroundpress.blogspot.com/2024/02/new-from-aboveground-press-in-margins.html?m=1

Programmatic Governance in GCP
~~
Multicloud.7 Deployments, Configurations, Templates, glcoud, and API calls
~~
#deployment #resource #manager #governance #cloud #security #gcp #google #configuration #api #gcloud #template #constraint

https://medium.com/cloud-security/programmatic-governance-in-gcp-176f1180bc19