{"id":1035,"date":"2024-07-31T10:12:57","date_gmt":"2024-07-31T08:12:57","guid":{"rendered":"https:\/\/blog.sutilweb.eu\/?page_id=1035"},"modified":"2024-07-31T10:12:58","modified_gmt":"2024-07-31T08:12:58","slug":"10-relaciones","status":"publish","type":"page","link":"https:\/\/sutilweb.eu\/index.php\/databases\/diseno-de-bases-de-datos\/10-relaciones\/","title":{"rendered":"10. Relaciones"},"content":{"rendered":"\n<p>Las <strong>relaciones<\/strong> son las <strong>asociaciones<\/strong> que hacemos entre las <strong>entidades<\/strong> para poder vincular y recuperar los datos. Por ejm en un <em>sistema de gesti\u00f3n escolar<\/em> podemos tener una <strong>entidad<\/strong> donde tengamos toda la informaci\u00f3n personal de las personas (nombre, direcci\u00f3n&#8230;), pero en ese sistema escolar vamos a tener diferentes perfiles de usuario (estudiantes, profesores, administrativos). Esa <strong>relaci\u00f3n<\/strong> entre la <strong>entidad<\/strong> perfiles y la <strong>entidad<\/strong> personas se lleva a cabo mediante estas <strong>relaciones.<\/strong><\/p>\n\n\n\n<!--more-->\n\n\n\n<p>Para crear esta <strong>relaci\u00f3n sem\u00e1ntica<\/strong> utilizamos un <strong>verbo<\/strong> para <strong>relacionar<\/strong> la <strong>entidad<\/strong> en cuesti\u00f3n.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Tipos de relaciones<\/h2>\n\n\n\n<p>Tenemos 3 tipos de relaciones:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Relaci\u00f3n uno a uno<\/strong>: una persona posee un \u00fanico tipo de perfil (ejm, una persona es un estudiante), las matr\u00edculas de un autom\u00f3vil es otro ejm.<\/li>\n\n\n\n<li><strong>Relaci\u00f3n uno a muchos<\/strong>: a una empresa se le han generado diferentes facturas a diferentes empresas que le dan servicio.<\/li>\n\n\n\n<li><strong>Relaci\u00f3n muchos a muchos<\/strong>: cuando se da este caso tenemos que pensar si est\u00e1 bien optimizado nuestro <strong>modelado de datos,<\/strong> porque generalmente puede significar que tenemos que volver a <strong>normalizar<\/strong> nuestro <strong>dise\u00f1o de bases de datos,<\/strong> o quiz\u00e1 utilizar un <strong>modelo no relacional,<\/strong> dependiendo de si tenemos que sacar muchos c\u00e1lculos como promedio, sueldos&#8230; Puede ser un primer indicador de que no estamos tomando un <strong>modelo de base de datos<\/strong> correcto. Puede ser por ejm una persona puede comprar varios productos a Amazon, pero a su vez, estos productos pueden ser comprados a varios clientes, es decir, muchos clientes pueden comprar muchos productos, y muchos productos pueden ser comprados por muchos clientes.<\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"<p>Las relaciones son las asociaciones que hacemos entre las entidades para poder vincular y recuperar los datos. Por ejm en [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":1009,"menu_order":9,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_uag_custom_page_level_css":"","site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"class_list":["post-1035","page","type-page","status-publish","hentry"],"uagb_featured_image_src":{"full":false,"thumbnail":false,"medium":false,"medium_large":false,"large":false,"1536x1536":false,"2048x2048":false},"uagb_author_info":{"display_name":"Sutil Web","author_link":"https:\/\/sutilweb.eu\/index.php\/author\/sutilweb\/"},"uagb_comment_info":0,"uagb_excerpt":"Las relaciones son las asociaciones que hacemos entre las entidades para poder vincular y recuperar los datos. Por ejm en [&hellip;]","_links":{"self":[{"href":"https:\/\/sutilweb.eu\/index.php\/wp-json\/wp\/v2\/pages\/1035","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/sutilweb.eu\/index.php\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/sutilweb.eu\/index.php\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/sutilweb.eu\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/sutilweb.eu\/index.php\/wp-json\/wp\/v2\/comments?post=1035"}],"version-history":[{"count":2,"href":"https:\/\/sutilweb.eu\/index.php\/wp-json\/wp\/v2\/pages\/1035\/revisions"}],"predecessor-version":[{"id":1037,"href":"https:\/\/sutilweb.eu\/index.php\/wp-json\/wp\/v2\/pages\/1035\/revisions\/1037"}],"up":[{"embeddable":true,"href":"https:\/\/sutilweb.eu\/index.php\/wp-json\/wp\/v2\/pages\/1009"}],"wp:attachment":[{"href":"https:\/\/sutilweb.eu\/index.php\/wp-json\/wp\/v2\/media?parent=1035"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}