Os desenvolvedores do projeto SQLite come\u00e7aram a testar um backend experimental chamado HCtree, que suporta bloqueio a n\u00edvel de linhas e proporciona um alto n\u00edvel de paralelismo ao processar solicita\u00e7\u00f5es. O novo backend visa aumentar a efici\u00eancia do uso do SQLite em sistemas cliente-servidor, onde \u00e9 necess\u00e1rio lidar com um grande n\u00famero de solicita\u00e7\u00f5es simult\u00e2neas para grava\u00e7\u00e3o no banco de dados. <\/p>\n
As estruturas b-tree, inicialmente utilizadas no SQLite para armazenar dados, n\u00e3o s\u00e3o adequadas para esse tipo de carga, o que limita o SQLite \u00e0 grava\u00e7\u00e3o em um \u00fanico fluxo. Como experimento, os desenvolvedores come\u00e7aram a desenvolver uma solu\u00e7\u00e3o alternativa, utilizando estruturas HC-tree de armazenamento, mais adequadas para paralelizar opera\u00e7\u00f5es de grava\u00e7\u00e3o. <\/p>\n
Para organizar a execu\u00e7\u00e3o simult\u00e2nea de v\u00e1rias opera\u00e7\u00f5es em HCtree, utiliza-se um mecanismo de separa\u00e7\u00e3o de transa\u00e7\u00f5es, que faz uso de bloqueios a n\u00edvel de p\u00e1ginas e \u00e9 similar ao MVCC (controle de concorr\u00eancia multimodal), mas utiliza verifica\u00e7\u00f5es de transa\u00e7\u00f5es baseadas em chaves e intervalos de chaves em vez de conjuntos de p\u00e1ginas. As opera\u00e7\u00f5es de leitura e grava\u00e7\u00e3o s\u00e3o realizadas em rela\u00e7\u00e3o ao instant\u00e2neo do banco de dados, cujas altera\u00e7\u00f5es se tornam vis\u00edveis no banco de dados principal apenas ap\u00f3s a conclus\u00e3o da transa\u00e7\u00e3o. <\/p>\n
Os clientes podem usar tr\u00eas opera\u00e7\u00f5es para abrir transa\u00e7\u00f5es: <\/p>\n
HCtree suporta replica\u00e7\u00e3o estilo \u00abmaster-slave\u00bb, permitindo a transfer\u00eancia de transa\u00e7\u00f5es para outro banco de dados e mantendo bancos de dados secund\u00e1rios sincronizados com o banco de dados principal. HCtree tamb\u00e9m remove a limita\u00e7\u00e3o do tamanho do banco de dados \u2014 em vez de identificadores de p\u00e1ginas de dados de 32 bits, HCtree aplica identificadores de 48 bits, aumentando o tamanho m\u00e1ximo do banco de dados de 16 tebibytes para 1 exbibyte (um milh\u00e3o de tebibytes). Espera-se que o desempenho do SQLite com o backend HCtree n\u00e3o seja inferior ao do backend cl\u00e1ssico de thread \u00fanica. Clientes SQLite com suporte a HCtree poder\u00e3o acessar tanto bancos de dados baseados na estrutura HC-tree quanto bancos de dados SQLite antigos. \u0420\u0430\u0437\u0440\u0430\u0431\u043e\u0442\u0447\u0438\u043a\u0438 \u043f\u0440\u043e\u0435\u043a\u0442\u0430 SQLite \u043d\u0430\u0447\u0430\u043b\u0438 \u0442\u0435\u0441\u0442\u0438\u0440\u043e\u0432\u0430\u043d\u0438\u0435 \u044d\u043a\u0441\u043f\u0435\u0440\u0438\u043c\u0435\u043d\u0442\u0430\u043b\u044c\u043d\u043e\u0433\u043e \u0431\u044d\u043a\u0435\u043d\u0434\u0430 HCtree, \u043f\u043e\u0434\u0434\u0435\u0440\u0436\u0438\u0432\u0430\u044e\u0449\u0435\u0433\u043e \u0431\u043b\u043e\u043a\u0438\u0440\u043e\u0432\u043a\u0443 \u043d\u0430 \u0443\u0440\u043e\u0432\u043d\u0435 \u0441\u0442\u0440\u043e\u043a (row) \u0438 \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0438\u0432\u0430\u044e\u0449\u0435\u0433\u043e \u0432\u044b\u0441\u043e\u043a\u0438\u0439 \u0443\u0440\u043e\u0432\u0435\u043d\u044c \u0440\u0430\u0441\u043f\u0430\u0440\u0430\u043b\u043b\u0435\u043b\u0438\u0432\u0430\u043d\u0438\u044f \u043f\u0440\u0438 \u043e\u0431\u0440\u0430\u0431\u043e\u0442\u043a\u0435 \u0437\u0430\u043f\u0440\u043e\u0441\u043e\u0432. \u041d\u043e\u0432\u044b\u0439 \u0431\u044d\u043a\u0435\u043d\u0434 \u043d\u0430\u0446\u0435\u043b\u0435\u043d \u043d\u0430 \u043f\u043e\u0432\u044b\u0448\u0435\u043d\u0438\u0435 \u044d\u0444\u0444\u0435\u043a\u0442\u0438\u0432\u043d\u043e\u0441\u0442\u0438 \u0438\u0441\u043f\u043e\u043b\u044c\u0437\u043e\u0432\u0430\u043d\u0438\u044f SQLite \u0432 \u043a\u043b\u0438\u0435\u043d\u0442-\u0441\u0435\u0440\u0432\u0435\u0440\u043d\u044b\u0445 \u0441\u0438\u0441\u0442\u0435\u043c\u0430\u0445, \u0432 \u043a\u043e\u0442\u043e\u0440\u044b\u0445 \u043f\u0440\u0438\u0445\u043e\u0434\u0438\u0442\u0441\u044f \u043e\u0431\u0440\u0430\u0431\u0430\u0442\u044b\u0432\u0430\u0442\u044c \u0431\u043e\u043b\u044c\u0448\u043e\u0435 \u0447\u0438\u0441\u043b\u043e \u043e\u0434\u043d\u043e\u0432\u0440\u0435\u043c\u0435\u043d\u043d\u044b\u0445 \u0437\u0430\u043f\u0440\u043e\u0441\u043e\u0432 \u043a \u0411\u0414 \u043d\u0430 \u0437\u0430\u043f\u0438\u0441\u044c. \u0421\u0442\u0440\u0443\u043a\u0442\u0443\u0440\u044b b-tree, \u0438\u0437\u043d\u0430\u0447\u0430\u043b\u044c\u043d\u043e \u043f\u0440\u0438\u043c\u0435\u043d\u044f\u0435\u043c\u044b\u0435 \u0432 SQLite \u0434\u043b\u044f \u0445\u0440\u0430\u043d\u0435\u043d\u0438\u044f \u0434\u0430\u043d\u043d\u044b\u0445, \u043d\u0435 […]<\/p>\n","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[702],"tags":[],"class_list":["post-106417","post","type-post","status-publish","format-standard","hentry","category-news"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\n","aioseo_head_json":{"title":"\ud83e\udd47Os desenvolvedores do SQLite est\u00e3o aprimorando o backend HC-tree com suporte para opera\u00e7\u00f5es de grava\u00e7\u00e3o paralelas | ProHoster","description":"Os desenvolvedores do projeto SQLite iniciaram testes de um backend experimental HCtree, que suporta bloqueio a n\u00edvel de linha e oferece um alto n\u00edvel de paraleliza\u00e7\u00e3o no processamento de consultas.","canonical_url":"https:\/\/prohoster.info\/pt\/blog\/news\/razrabotchiki-sqlite-razvivayut-bekend-hc-tree-s-podderzhkoj-parallelnyh-operaczij-zapisi","robots":"max-image-preview:large","keywords":"","webmasterTools":{"miscellaneous":""},"schema":null,"og:locale":"pt_PT","og:site_name":"ProHoster | \u041a\u0443\u043f\u0438\u0442\u044c \u043d\u0430\u0434\u0435\u0436\u043d\u044b\u0439 \u0445\u043e\u0441\u0442\u0438\u043d\u0433 \u0434\u043b\u044f \u0441\u0430\u0439\u0442\u043e\u0432 \u0441 \u0437\u0430\u0449\u0438\u0442\u043e\u0439 \u043e\u0442 DDoS, VPS VDS \u0441\u0435\u0440\u0432\u0435\u0440\u044b","og:type":"article","og:title":"\ud83e\udd47\u0420\u0430\u0437\u0440\u0430\u0431\u043e\u0442\u0447\u0438\u043a\u0438 SQLite \u0440\u0430\u0437\u0432\u0438\u0432\u0430\u044e\u0442 \u0431\u044d\u043a\u0435\u043d\u0434 HC-tree \u0441 \u043f\u043e\u0434\u0434\u0435\u0440\u0436\u043a\u043e\u0439 \u043f\u0430\u0440\u0430\u043b\u043b\u0435\u043b\u044c\u043d\u044b\u0445 \u043e\u043f\u0435\u0440\u0430\u0446\u0438\u0439 \u0437\u0430\u043f\u0438\u0441\u0438 | ProHoster","og:description":"\u0420\u0430\u0437\u0440\u0430\u0431\u043e\u0442\u0447\u0438\u043a\u0438 \u043f\u0440\u043e\u0435\u043a\u0442\u0430 SQLite \u043d\u0430\u0447\u0430\u043b\u0438 \u0442\u0435\u0441\u0442\u0438\u0440\u043e\u0432\u0430\u043d\u0438\u0435 \u044d\u043a\u0441\u043f\u0435\u0440\u0438\u043c\u0435\u043d\u0442\u0430\u043b\u044c\u043d\u043e\u0433\u043e \u0431\u044d\u043a\u0435\u043d\u0434\u0430 HCtree, \u043f\u043e\u0434\u0434\u0435\u0440\u0436\u0438\u0432\u0430\u044e\u0449\u0435\u0433\u043e \u0431\u043b\u043e\u043a\u0438\u0440\u043e\u0432\u043a\u0443 \u043d\u0430 \u0443\u0440\u043e\u0432\u043d\u0435 \u0441\u0442\u0440\u043e\u043a (row) \u0438 \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0438\u0432\u0430\u044e\u0449\u0435\u0433\u043e \u0432\u044b\u0441\u043e\u043a\u0438\u0439 \u0443\u0440\u043e\u0432\u0435\u043d\u044c \u0440\u0430\u0441\u043f\u0430\u0440\u0430\u043b\u043b\u0435\u043b\u0438\u0432\u0430\u043d\u0438\u044f \u043f\u0440\u0438 \u043e\u0431\u0440\u0430\u0431\u043e\u0442\u043a\u0435 \u0437\u0430\u043f\u0440\u043e\u0441\u043e\u0432.","og:url":"https:\/\/prohoster.info\/pt\/blog\/news\/razrabotchiki-sqlite-razvivayut-bekend-hc-tree-s-podderzhkoj-parallelnyh-operaczij-zapisi","og:image":"https:\/\/prohoster.info\/wp-content\/uploads\/2021\/11\/logo-350.jpg","og:image:secure_url":"https:\/\/prohoster.info\/wp-content\/uploads\/2021\/11\/logo-350.jpg","og:image:width":350,"og:image:height":350,"article:published_time":"2023-01-19T16:48:11+00:00","article:modified_time":"2023-01-24T11:52:43+00:00","article:publisher":"https:\/\/www.facebook.com\/prohoster","article:author":"https:\/\/www.facebook.com\/prohoster"},"aioseo_meta_data":[],"gt_translate_keys":[{"key":"link","format":"url"}],"_links":{"self":[{"href":"https:\/\/prohoster.info\/pt\/wp-json\/wp\/v2\/posts\/106417","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/prohoster.info\/pt\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/prohoster.info\/pt\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/prohoster.info\/pt\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/prohoster.info\/pt\/wp-json\/wp\/v2\/comments?post=106417"}],"version-history":[{"count":0,"href":"https:\/\/prohoster.info\/pt\/wp-json\/wp\/v2\/posts\/106417\/revisions"}],"wp:attachment":[{"href":"https:\/\/prohoster.info\/pt\/wp-json\/wp\/v2\/media?parent=106417"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/prohoster.info\/pt\/wp-json\/wp\/v2\/categories?post=106417"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/prohoster.info\/pt\/wp-json\/wp\/v2\/tags?post=106417"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
\n
Fonte: opennet.ru<\/a> <\/p>","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"excerpt":{"rendered":"