{"id":12029,"date":"2013-02-10T10:26:22","date_gmt":"2013-02-10T10:26:22","guid":{"rendered":"https:\/\/www.techopedia.com\/definition\/armstrongs-axiom\/"},"modified":"2017-06-20T14:36:59","modified_gmt":"2017-06-20T14:36:59","slug":"armstrongs-axiom","status":"publish","type":"definition","link":"https:\/\/www.techopedia.com\/definition\/27247\/armstrongs-axiom","title":{"rendered":"Armstrong’s Axiom"},"content":{"rendered":"

What Does Armstrong’s Axiom Mean?<\/span><\/h2>\n

Armstrong\u2019s Axiom is a mathematical notation used to find the functional dependencies in a database. Conceived by William W. Armstrong, it is a list of axioms or inference rules that can be implemented on any relational database. It is denoted by the symbol F+.\n<\/p>\n

Techopedia Explains Armstrong’s Axiom<\/span><\/h2>\n

Armstrong\u2019s Axiom is used to analyze, refine and maintain relational databases. It has three major modes or inferences applied on a set of data. They are as follows:\n<\/p>\n

    \n
  • Axiom of Reflexivity: If user name (A) and title (B) represent a person’s name, then the relationship between both (A and B) is of little importance.<\/li>\n
  • Axiom of Augmentation: If a user ID defines a person’s name, then the user ID with email quota define the person\u2019s name and email quota.<\/li>\n
  • Axiom of Transitivity: If a user ID determines a person’s name, and a person’s name defines the department, then the department can define the user ID.<\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"

    What Does Armstrong’s Axiom Mean? Armstrong\u2019s Axiom is a mathematical notation used to find the functional dependencies in a database. Conceived by William W. Armstrong, it is a list of axioms or inference rules that can be implemented on any relational database. It is denoted by the symbol F+. Techopedia Explains Armstrong’s Axiom Armstrong\u2019s Axiom […]<\/p>\n","protected":false},"author":7813,"featured_media":0,"comment_status":"open","ping_status":"closed","template":"","format":"standard","meta":{"_acf_changed":false,"_lmt_disableupdate":"","_lmt_disable":"","om_disable_all_campaigns":false,"footnotes":""},"definitioncat":[227,222,228],"class_list":["post-12029","definition","type-definition","status-publish","format-standard","hentry","definitioncat-data-management","definitioncat-database","definitioncat-risk-management"],"acf":[],"yoast_head":"\nWhat is Armstrong's Axiom? - Definition from Techopedia<\/title>\n<meta name=\"description\" content=\"This definition explains the meaning of Armstrong's Axiom and why it matters.\" \/>\n<meta name=\"robots\" content=\"noindex, follow\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Armstrong's Axiom\" \/>\n<meta property=\"og:description\" content=\"This definition explains the meaning of Armstrong's Axiom and why it matters.\" \/>\n<meta property=\"og:url\" content=\"https:\/\/www.techopedia.com\/definition\/27247\/armstrongs-axiom\" \/>\n<meta property=\"og:site_name\" content=\"Techopedia\" \/>\n<meta property=\"article:publisher\" content=\"https:\/\/www.facebook.com\/techopedia\/\" \/>\n<meta property=\"article:modified_time\" content=\"2017-06-20T14:36:59+00:00\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:site\" content=\"@techopedia\" \/>\n<meta name=\"twitter:label1\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data1\" content=\"1 minute\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\/\/schema.org\",\"@graph\":[{\"@type\":\"Article\",\"@id\":\"https:\/\/www.techopedia.com\/definition\/27247\/armstrongs-axiom#article\",\"isPartOf\":{\"@id\":\"https:\/\/www.techopedia.com\/definition\/27247\/armstrongs-axiom\"},\"author\":{\"name\":\"Margaret Rouse\",\"@id\":\"https:\/\/www.techopedia.com\/#\/schema\/person\/f5dd538e31ee352d105b8af36c4268a5\"},\"headline\":\"Armstrong’s Axiom\",\"datePublished\":\"2013-02-10T10:26:22+00:00\",\"dateModified\":\"2017-06-20T14:36:59+00:00\",\"mainEntityOfPage\":{\"@id\":\"https:\/\/www.techopedia.com\/definition\/27247\/armstrongs-axiom\"},\"wordCount\":170,\"commentCount\":0,\"publisher\":{\"@id\":\"https:\/\/www.techopedia.com\/#organization\"},\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"CommentAction\",\"name\":\"Comment\",\"target\":[\"https:\/\/www.techopedia.com\/definition\/27247\/armstrongs-axiom#respond\"]}],\"articleSection\":\"\"},{\"@type\":\"WebPage\",\"@id\":\"https:\/\/www.techopedia.com\/definition\/27247\/armstrongs-axiom\",\"url\":\"https:\/\/www.techopedia.com\/definition\/27247\/armstrongs-axiom\",\"name\":\"What is Armstrong's Axiom? 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