[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"detail-sidebar-cat-0-en-105":3,"doc-seo-655951-105":59,"doc-detail-655951-en":130},{"code":4,"msg":5,"data":6},0,"success",[7,13,18,23,28,33,38,43,48,51,55],{"id":8,"doc_module":4,"doc_module_name":9,"category_name":10,"show_sort_weight":11,"slug":12},1,"Document","Story & Novel",90,"story-novel",{"id":14,"doc_module":4,"doc_module_name":9,"category_name":15,"show_sort_weight":16,"slug":17},2,"Literature",80,"literature",{"id":19,"doc_module":4,"doc_module_name":9,"category_name":20,"show_sort_weight":21,"slug":22},4,"Exam",70,"exam",{"id":24,"doc_module":4,"doc_module_name":9,"category_name":25,"show_sort_weight":26,"slug":27},5,"Comic",60,"comic",{"id":29,"doc_module":4,"doc_module_name":9,"category_name":30,"show_sort_weight":31,"slug":32},6,"Technology",50,"technology",{"id":34,"doc_module":4,"doc_module_name":9,"category_name":35,"show_sort_weight":36,"slug":37},7,"Healthcare",40,"healthcare",{"id":39,"doc_module":4,"doc_module_name":9,"category_name":40,"show_sort_weight":41,"slug":42},8,"Research & Report",30,"research-report",{"id":44,"doc_module":4,"doc_module_name":9,"category_name":45,"show_sort_weight":46,"slug":47},9,"Religion & Spirituality",20,"religion-spirituality",{"id":46,"doc_module":4,"doc_module_name":9,"category_name":49,"show_sort_weight":46,"slug":50},"World Cup","world-cup",{"id":52,"doc_module":4,"doc_module_name":9,"category_name":53,"show_sort_weight":52,"slug":54},10,"Lifestyle","lifestyle",{"id":56,"doc_module":4,"doc_module_name":9,"category_name":57,"show_sort_weight":24,"slug":58},19,"General","general",{"code":4,"msg":60,"data":61},"ok",{"site_id":62,"language":63,"slug":64,"title":65,"keywords":66,"description":67,"schema_data":68,"social_meta":123,"head_meta":125,"extra_data":127,"updated_unix":129},105,"en","entity-relationship-diagram-database-design-and-constraints","Entity Relationship Diagram - Database Design and Constraints","","Entity Relationship Diagram lecture explains how database design decides the tables to create by capturing application-required information with minimal redundancy. It introduces ER diagrams as a pictorial representation of database information, useful for concise yet accurate overall descriptions and transformation into relational schemas. The content defines entities and entity sets with attributes and primary keys, then formalizes relationships and relationship sets with examples. It further covers binary relationship sets and their cardinality constraints (one-to-one, one-to-many, many-to-one, many-to-many), along with participation constraints (total, partial).",{"@graph":69,"@context":122},[70,84,105],{"@type":71,"itemListElement":72},"BreadcrumbList",[73,77,79,82],{"item":74,"name":75,"@type":76,"position":8},"https://docshare.wps.com","Home","ListItem",{"item":78,"name":9,"@type":76,"position":14},"https://docshare.wps.com/document/",{"item":80,"name":30,"@type":76,"position":81},"https://docshare.wps.com/document/technology/",3,{"item":83,"name":65,"@type":76,"position":19},"https://docshare.wps.com/document/entity-relationship-diagram-database-design-and-constraints/655951/",{"url":83,"name":65,"@type":85,"image":86,"author":91,"headline":65,"publisher":94,"fileFormat":97,"inLanguage":63,"description":67,"dateModified":98,"datePublished":99,"encodingFormat":97,"isAccessibleForFree":100,"interactionStatistic":101},"DigitalDocument",{"url":87,"@type":88,"width":89,"height":90},"https://docshare.wps.com/thumbnails/entity-relationship-diagram-database-design-and-constraints/655951.png","ImageObject",300,407,{"name":92,"@type":93},"Emma Wilson","Person",{"url":74,"name":95,"@type":96},"DocShare","Organization","application/pdf","2026-10-30","2026-10-25",true,{"@type":102,"interactionType":103,"userInteractionCount":19},"InteractionCounter",{"@type":104},"ViewAction",{"@type":106,"mainEntity":107},"FAQPage",[108,114,118],{"name":109,"@type":110,"acceptedAnswer":111},"What are the two main principles behind database design mentioned in the lecture?","Question",{"text":112,"@type":113},"The lecture states that database design should capture all information needed by the underlying application and achieve it with little redundancy.","Answer",{"name":115,"@type":110,"acceptedAnswer":116},"How does an ER diagram help in database design?",{"text":117,"@type":113},"An ER diagram provides a concise yet accurate pictorial representation of information to be captured, and (most of it) can be transformed into the relational schema.",{"name":119,"@type":110,"acceptedAnswer":120},"What constraints are used for binary relationship sets in the lecture?",{"text":121,"@type":113},"For binary relationship sets (n=2), the lecture describes cardinality constraints (one-to-one, one-to-many, many-to-one, many-to-many) and participation constraints (total, partial).","https://schema.org",{"og:url":83,"og:type":124,"og:title":65,"og:site_name":95,"og:description":67},"article",{"robots":126,"canonical":83},"index,follow",{"doc_id":128,"site_id":62},655951,1793030382,{"code":4,"msg":5,"data":131},{"doc_id":128,"user_id":132,"nickname":92,"user_avatar":133,"doc_module":4,"category_id":29,"category_name":30,"doc_title":65,"doc_description":67,"doc_content":134,"file_id":135,"file_url":136,"file_type":137,"file_size":138,"view_count":19,"is_deleted":4,"is_public":8,"is_downloadable":8,"audit_status":8,"page_count":139,"language":140,"language_code":63,"site_id":62,"html_lang":63,"table_of_contents":141,"faqs":142,"seo_title":143,"seo_description":67,"update_tm":144,"read_time":145},3848291630094,"https://eur-avatar.wpscdn.com/davatar_085a072bc5b1113ac321206ff7593b45","Entity Relationship Diagram  \nYufei Tao  \nDepartment of Computer Science and Engineering Chinese University of Hong Kong  \nEntity Relationship Diagram  \nA primary goal of database design is to decide what tables to create. Usually, there are two principles:  \n1 Capture all the information that needs to be captured by the underlying application.  \n2 Achieve the above with little redundancy.  \nThe 􀀌rst principle is enforced with an entity relationship (ER) diagram , while the second with normalization.  \nThis lecture focuses on the ER diagram.  \nEntity Relationship Diagram  \nAn ER diagram is a pictorial representation of the information that can be captured by a database. Such a \\picture\" serves two purposes:  \n It allows database professionals to describe an overall design concisely yet accurately.  \n (Most of) it can be easily transformed into the relational schema.  \nEntity Relationship Diagram  \nAn entity is an atomic object that needs to be represented in the database. An entity set is a set of entities with common attributes.  \nFor example, a professor is an entity. PROF is an entity set with all the professors.  \nThe following shows how to describe in an ER-diagram the entity set PROF with attributes pid, hkid, dept, rank, salary, with pid being the primary key.  \nEntity Relationship Diagram  \nA relationship is an association among several entities that needs to be represented in the database. We will denote the relationship as  \n(e1 ; e2 ; :::; en ), where e1 ; ::: en are the entities participating in the relationship.  \nA relationship set is a set R of relationships (e1 ; :::; en ), where each ei comes from the same entity set Ei , for 1 􀀔 i 􀀔 n.  \nExample: The following shows a relationship set R between entity sets A and B .  \nB  \nR = f (a1 ; b1 ) ; (a1 ; b4 ) ; (a2 ; b2 ) ; (a2 ; b4 ) ; (a3 ; b3 )g.         \nEntity Relationship Diagram  \nThe next few slides will discuss binary relationship sets, i.e. , n = 2 . For such relationship sets, we can impose two types of constraints.  \nCardinality constraint:  \n One-to-one.  \n One-to-many (or conversely, many-to-one) .  \n many-to-many.  \nParticipation constraint:  \n Total.  \n Partial.  \nWe will 􀀌rst talk about cardinality constraints.  \nEntity Relationship Diagram  \nA relationship set R between entity sets A and B is one-to-one if every entity in A and B can participate in at most one relationship in R.  \nB  \nExample: Husbands and wifes.  \nEntity Relationship Diagram  \nA relationship set R between entity sets A and B is one-to-many if every entity in A can participate in any number of relationships in R, but an  \nentity in B can participate in at most one relationship in R.  \nB  \nExample: Parents and Children.  \nMany-to-one is de􀀌ned analogously.  \nEntity Relationship Diagram  \nA relationship set R between entity sets A and B is many-to-many if every entity in A and B can participate in any number of relationships in R.  \nB  \nExample: Students and classes.  \nEntity Relationship Diagram","cbCain31cBUx1V7e","https://ap.wps.com/l/cbCain31cBUx1V7e","pdf",230510,17,"English","# Entity Relationship Diagram Overview\n## Purpose and Transformation to Relational Schema\n## Entities and Entity Sets\n## Relationships and Relationship Sets\n# Binary Relationship Sets and Constraints\n## Cardinality Constraints\n## Participation Constraints","[{\"question\":\"What are the two main principles behind database design mentioned in the lecture?\",\"answer\":\"The lecture states that database design should capture all information needed by the underlying application and achieve it with little redundancy.\"},{\"question\":\"How does an ER diagram help in database design?\",\"answer\":\"An ER diagram provides a concise yet accurate pictorial representation of information to be captured, and (most of it) can be transformed into the relational schema.\"},{\"question\":\"What constraints are used for binary relationship sets in the lecture?\",\"answer\":\"For binary relationship sets (n=2), the lecture describes cardinality constraints (one-to-one, one-to-many, many-to-one, many-to-many) and participation constraints (total, partial).\"}]","Entity Relationship Diagram - Database Design and Constraints | PDF",1792965071,43]