Database theory encapsulates a broad range of topics related to the study and research of the theoretical realm of databases and database management systems.
Theoretical aspects of data management include, among other areas, the foundations of query languages, computational complexity and expressive power of queries, finite model theory, database design theory, dependency theory, foundations of concurrency control and database recovery, deductive databases, temporal and spatial databases, real-time databases, managing uncertain data and probabilistic databases, and Web data.
Most research work has traditionally been based on the relational model, since this model is usually considered the simplest and most foundational model of interest. Corresponding results for other data models, such as object-oriented or semi-structured models, or, more recently, graph data models and XML, are often derivable from those for the relational model.[1]
Database theory helps one to understand the complexity and power of query languages and their connection to logic. Starting from relational algebra and first-order logic (which are equivalent by Codd's theorem) and the insight that important queries such as graph reachability are not expressible in this language,[2] more powerful language based on logic programming and fixpoint logic such as Datalog were studied.[3] The theory also explores foundations of query optimization and data integration. Here most work studied conjunctive queries, which admit query optimization even under constraints using the chase algorithm.
The main research conferences in the area are the ACM Symposium on Principles of Database Systems (PODS) and the International Conference on Database Theory (ICDT).
Релятиві́стський ефе́кт — будь-яке явище у фізиці, кількісна характеристика якого визначається відношенням швидкості руху частинок фізичної системи до швидкості світла. Релятивістські ефекти відсутні для нерухомих частинок і загалом незначні для частинок, швидкіст
Nodaviridae Komposisi genom virus ICTVpositive-sense single-stranded RNA virus (en) TaksonomiSuperdomainBiotaDomainVirusFamiliNodaviridae lbs Nodaviridae adalah famili virus yang menginfeksi berbagai vertebrata dan invertebrata. Dalam famili virus ini, terdapat genus Alphanodavirus yang menginfeksi serangga, dan Betanodavirus yang menginfeksi ikan. Nama Nodaviridae didapatkan dari virus pertama yang diisolasi dari nyamuk Culex, yaitu virus Nodamura (Nodamura virus, NV). Virus ini tidak memiliki …
Da'i BachtiarDuta Besar Indonesia untuk Malaysia ke-15Masa jabatan8 April 2008 – 27 September 2012PresidenSusilo Bambang YudhoyonoPendahuluTatang Budie Utama RazakPenggantiHerman PrayitnoKepala Kepolisian Negara Republik Indonesia ke-17Masa jabatan29 November 2001 – 7 Juli 2005PresidenMegawati Soekarno PutriSusilo Bambang YudhoyonoPendahuluChairuddin IsmailPenggantiSutanto Informasi pribadiLahir25 Januari 1950 (umur 73)Indramayu, Jawa BaratSuami/istriIda Yulian…
Este artículo o sección necesita referencias que aparezcan en una publicación acreditada.Este aviso fue puesto el 5 de diciembre de 2021. Argula von Grumbach Información personalNacimiento 1492 Burg Ehrenfels (Alemania) Fallecimiento 1554 Zeilitzheim (Alemania) Nacionalidad AlemanaReligión Luteranismo Información profesionalOcupación Dama de compañía, poeta y escritora Área Poesía [editar datos en Wikidata] Argula von Grumbach (1492 - c. 1564)[1] fue una escritora y n…
Coordenadas: 45° 12' N 9° 19' E Copiano Comuna Localização CopianoLocalização de Copiano na Itália Coordenadas 45° 12' N 9° 19' E Região Lombardia Província Pavia Características geográficas Área total 4 km² População total 1 364 hab. Densidade 341 hab./km² Altitude 74 m Outros dados Comunas limítrofes Filighera, Genzone, Gerenzago, Magherno, Vistarino Código ISTAT 018053 Código postal 27010 Prefixo telefnico 0382 …
◄ Junho ► Dom Seg Ter Qua Qui Sex Sáb 28 29 30 31 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 1 Ano: 2023 Década: 2020 Século: XXI Milênio: 3.º 21 de junho é o 172.º dia do ano no calendário gregoriano (173.º em anos bissextos). Faltam 193 dias para acabar o ano. É o dia do solstício de junho, quando começa o verão no hemisfério norte e o inverno no hemisfério sul. Portanto, é o dia mais longo e a noite mais curta no hemisfério norte e o …
يفتقر محتوى هذه المقالة إلى الاستشهاد بمصادر. فضلاً، ساهم في تطوير هذه المقالة من خلال إضافة مصادر موثوق بها. أي معلومات غير موثقة يمكن التشكيك بها وإزالتها. (يناير 2022) قائمة كل الأشجار على 2،3،4 مميزة الرؤوس: 2 2 − 2 = 1 {\displaystyle 2^{2-2}=1} شجرة واحدة برأسين, 3 3 − 2 = 3 {\displaystyle 3^{3-2}=3}
History of women's right to vote in Canada Presentation of petition by Political Equality League for enfranchisement of women, Winnipeg, 23 December 1915 Political cartoon commenting on women's voting rights in Quebec Women's suffrage in Canada occurred at different times in different jurisdictions to different demographics of women. Women's right to vote began in the three prairie provinces. In 1916, suffrage was earned by women in Manitoba, Saskatchewan, and Alberta. The federal government gra…
Audrey ChapmanLahir(1899-03-02)2 Maret 1899Philadelphia, Pennsylvania, A.S.Meninggal10 Agustus 1993(1993-08-10) (umur 94)Riverside, California, A.S.KebangsaanAmerikaPekerjaanAktrisSuami/istriRichard Evan Roberts (1922 - ?) The Money-Changers by Jack Conway, 1920 Audrey Chapman (2 Maret 1899 – 10 Agustus 1993) adalah seorang aktris dalam film pada era film bisu dari Philadelphia, Pennsylvania. Keponakan dari Hampton Del Ruth dan Roy Del Ruth,[1] Chapman adalah pu…
PS BatamNama lengkapPersatuan Sepakbola BatamJulukanKalajengking BarelangBerdiri1974; 48 tahun lalu (1974)StadionStadion Temenggung Abdul Jamal[1]Batam, Kepulauan Riau(Kapasitas: 2.800)PemilikAskot PSSI BatamKetuaRuslan Ali Wasyim[2]ManajerMulyadiLigaLiga 3 Kostum kandang Kostum tandang Persatuan Sepakbola Batam atau PS Batam adalah klub sepak bola Indonesia yang bermarkas di Stadion Temenggung Abdul Jamal, Kota Batam, Kepulauan Riau. Mereka saat ini bermain di Liga 3. Sejar…
Battles of Parczew, Jabłoń and MilanówPart of the Soviet Invasion of Poland in the European theatre of World War IIPolish infantry marching 1939DateSeptember 29–30, 1939Locationregion of Parczew, Jabłoń and Milanów, Lublin Voivodeship, PolandResult Tactical Polish victoryBelligerents Soviet Union PolandCommanders and leaders Unknown Franciszek KleebergStrength 143rd Rifle Division Independent Operational Group PolesieCasualties and losses 170 dead, 300 wounded, 100 POWs 20 de…
Si ce bandeau n'est plus pertinent, retirez-le. Cliquez ici pour en savoir plus. Cet article ne cite pas suffisamment ses sources (avril 2021). Si vous disposez d'ouvrages ou d'articles de référence ou si vous connaissez des sites web de qualité traitant du thème abordé ici, merci de compléter l'article en donnant les références utiles à sa vérifiabilité et en les liant à la section « Notes et références » En pratique : Quelles sources sont attendues ? Comment…
This article is about a New Zealand company. For similarly named companies in other countries, see Union Steamship Company. Union Steam Ship Company of New Zealand LimitedHouse flagIndustryShipping, freight and passenger servicesFounded1875FounderJames MillsDefunct2000HeadquartersDunedin (1875–1921)Wellington, New Zealand Head office, Water Street, Dunedin designed 1883 Five directors (back) of the Union Steam Ship Company in 1881, including John Richard Jones, John Cargill, and George McLean;…
UK video game magazine (1990–1992) This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed.Find sources: Mean Machines – news · newspapers · books · scholar · JSTOR (April 2017) (Learn how and when to remove this template message) Mean MachinesGary Harrod's cover artwork for Issue 12EditorJulian RignallCategoriesVideo game journal…
Divingat the Games of the XXVIII OlympiadVenueOlympic Aquatic CentreDates20 – 28 August 2004Competitors129 from 30 nations← 20002008 → Diving at the2004 Summer Olympics3 m springboardmenwomen10 m platformmenwomenSynchronized3 m springboardmenwomenSynchronized10 m platformmenwomenvte At the 2004 Summer Olympics, in Athens, eight diving events were contested during a competition that took place at the Olympic Aquatic Centre, from 20 to 28 August (14 and 16 August …
The Tajikistani records in swimming are the fastest ever performances of swimmers from Tajikistan, which are recognised and ratified by the National Swimming Federation of the Republic of Tajikistan. All records were set in finals unless noted otherwise. Long Course (50 m) Men Event Time Name Club Date Meet Location Ref 50m freestyle 25.43 h Olimjon Ishanov Tajikistan 21 August 2018 Asian Games Jakarta, Indonesia [1] 100m freestyle 58.36 h Alijon Khairulloev Tajikistan 24 Jul…
South Korean girl group Le SserafimLe Sserafim in June 2022From left to right: Kazuha, Yunjin, Sakura, Chaewon, and EunchaeBackground informationOriginSeoul, South KoreaGenresK-popYears active2022–presentLabelsSourceEMI/Universal[1]Geffen[2][3]Members Sakura Chaewon Yunjin Kazuha Eunchae Past membersGaramWebsiteOfficial website Le Sserafim (/lə ˈsɛrəfɪm/ luh SERR-uh-fim;[4] Korean: 르세라핌; RR: Leuserapim; MR: Lŭsera…
Piala SkotlandiaMulai digelar1874Wilayah SkotlandiaJuara bertahanCelticTim tersuksesCeltic(36 gelar)Situs webScottish Cup Piala Skotlandia 2013-14 Piala Skotlandia adalah kompetisi domestik sepak bola di Skotlandia. Mulai dikompetisikan sejak tahun 1873-1874. Final Piala Skotlandia Musim Juara Hasil Runner-up Lokasi Penonton Notes 1873–74 Queen's Park 2 – 0 Clydesdale Hampden Park (original) 2,500 [1][2] 1874–75 Queen's Park 3 – 0 Renton Hampden Park (original) 7,000…
Beauty pageant in Sweden Miss Grand SwedenPamela OliveraMiss Grand Sweden 2014Issabella GeorgssonMiss Grand Sweden 2015Formation2013TypeBeauty pageantHeadquartersStockholmLocationSwedenMembership Miss Grand InternationalOfficial language SwedishNational directorPeter HadwardGeneral directorKersten LibaParent organizationMiss Universe Sweden(2013 – 2014)Miss Queen of Scandinavia(2014 – 2021)WebsiteMissQueenOfScandinavia.com Jennie FrondellMiss Grand Sweden 2021 Miss Grand Sweden is a nat…
У этого термина существуют и другие значения, см. Панда. Малая панда Научная классификация Домен:ЭукариотыЦарство:ЖивотныеПодцарство:ЭуметазоиБез ранга:Двусторонне-симметричныеБез ранга:ВторичноротыеТип:ХордовыеПодтип:ПозвоночныеИнфратип:ЧелюстноротыеНадкласс:Четв…
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