[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"detail-sidebar-cat-0-en-105":3,"doc-seo-656084-105":59,"doc-detail-656084-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","cs34800-information-systems-entity-relationship-model-lecture-notes","CS34800 Information Systems - Entity-Relationship Model - Lecture Notes","","CS34800 Information Systems lecture notes covering announcements and upcoming assignments, then focusing on database conceptual modeling. The document explains main data model categories, distinguishing logical models from conceptual models, and highlights the Entity-Relationship model as a widely used conceptual approach. It defines entities, entity sets, attributes, primary keys, and how to depict them with rectangles and ovals. It further introduces relationships, relationship sets, and the idea that relationship values can be treated like tables connecting entity sets.",{"@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/cs34800-information-systems-entity-relationship-model-lecture-notes/656084/",{"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/cs34800-information-systems-entity-relationship-model-lecture-notes/656084.png","ImageObject",300,407,{"name":92,"@type":93},"BAd apple","Person",{"url":74,"name":95,"@type":96},"DocShare","Organization","application/pdf","2026-10-27","2026-10-25",true,{"@type":102,"interactionType":103,"userInteractionCount":81},"InteractionCounter",{"@type":104},"ViewAction",{"@type":106,"mainEntity":107},"FAQPage",[108,114,118],{"name":109,"@type":110,"acceptedAnswer":111},"What is the difference between logical models and conceptual models in DBMS data modeling?","Question",{"text":112,"@type":113},"Logical models describe, organize, and access data in a DBMS, and are independent of physical data structures. Conceptual models represent data independently from a specific DBMS, emphasizing semantics of real-world entities, attributes, and relationships.","Answer",{"name":115,"@type":110,"acceptedAnswer":116},"How are entities, entity sets, and attributes represented in ER diagrams?",{"text":117,"@type":113},"An entity set is represented as a rectangle, and attributes are shown as ovals. Primary key attributes are indicated by underlining.",{"name":119,"@type":110,"acceptedAnswer":120},"What is a relationship set, and how is its value interpreted?",{"text":121,"@type":113},"A relationship set connects two or more entity sets, represented by diamonds. Its value can be thought of like a table with one column per connected entity set and one row per connected combination of entities.","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},656084,1793053346,{"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":81,"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},19241458193282,"https://us-avatar.wpscdn.com/davatar_a8503ba1806abce46bf441b54a3ca4cd","CS34800 Information Systems  \nEntity-Relationship Model Prof. Chris Clifton  \n16 September 2016  \nAnnouncements  \n• Project 1 due at 11:59pm  \n– Some concerns about Part 2 (since we didn’t cover some of the material until last class) . Possible extension? (Frequency code DD)  \nA. Deadline for both Part 1 and Part 2 tonight  \n11:59pm  \nB. Part 1 due tonight 11:59pm, Part 2 tomorrow night 11:59pm  \n• Assignment 2 will be out later today  \n– Relational Algebra  \nMain categories of data  \nmodels  \n• Logical models: used to describe, organize and access data in DBMS; application programs refers to such models. They are independent from the physical data structures  \n– examples: relational data model, hierarchical data model, objectrelational data model  \n• Conceptual models: support the representation of data independently from specific DBMS. Their goal is to provide representations, which are rich in semantics, of the real word entities, their properties and relationships. These models are mainly used for the conceptual design of databases  \n– The Entity-Relationship is the most well known model in such category  \n Entity/Relationship Model  \nDiagrams to represent designs.  \n• Entity like object, = “thing.”  \n• Entity set like class = set of “similar”entities/objects.  \n• Attribute = property of entities in an entity set, similar to fields of a struct.  \n• In diagrams, entity set 􀁯 rectangle;  \nattribute 􀁯 oval. ID name phone  \nFall 2016 CS34800  \nEntity Sets  \n􀂄 An entity is an object that exists and is distinguishable from other objects.  \n􀁺 Example: specific person, company, event, plant  \n􀂄 An entity set is a set of entities of the same type that share the same properties.  \n􀁺 Example: set of all persons, companies, trees, holidays  \n􀂄 An entity is represented by a set of attributes; i.e. , descriptive properties possessed by all members of an entity set.  \n􀁺 Example:  \ninstructor = (ID, name, street, city, salary )  \ncourse= (course_id, title, credits)  \n􀂄 A subset of the attributes form a primary key of the entity  \nset; i.e. , uniquely identifiying each member of the set.  \nDatabase System Concepts 7.5 ©Silberschatz, Korth and Sudarshan  \nEntity Sets--instructor and student  \ninstructor_ID instructor_name student-ID student_name  \nDatabase System Concepts 7.6 ©Silberschatz, Korth and Sudarshan  \nEntity Sets  \n􀂄 Entities can be represented graphically as follows:  \n• Rectangles represent entity sets.  \n• Attributes listed inside entity rectangle  \n• Underline indicates primary key attributes  \nDatabase System Concepts 7.7 ©Silberschatz, Korth and Sudarshan  \nRelationships  \n• Connect two or more entity sets.  \n• Represented by diamonds.  \nRelationship Set  \nThink of the “value” of a relationship set as a table.  \n• One column for each of the connected entity sets.  \n• One row for each list of entities, one from each set, that are connected by the relationship.  \n\n| Students | Courses |\n| --- | --- |\n|  |  |\n| Sally | CS348 |\n| Sally | CS355 |\n| Joe | CS348 |\n| … | … |\n\nRelationship Sets  \n􀂄 A relationship is an association among several entities  \nExample:  \n44553 (Peltier )  advisor 22222 ( Einstein)  \nstudent entity relationship set instructor entity  \n􀂄 A relationship set is a mathematical relation among n 􀁴 2 entities, each taken from entity sets  \n{(e1 , e2 ,…en) | e 1 􀂏 E1 , e2 􀂏 E2 ,…, en 􀂏 En}  \nwhere (e1 , e2 ,…, en) is a relationship  \n􀁺 Example:  \n(44553,22222) 􀂏 advisor  \nDatabase System Concepts 7.10 ©Silberschatz, Korth and Sudarshan","cbCaihIQ5X2jn2cl","https://ap.wps.com/l/cbCaihIQ5X2jn2cl","pdf",6441938,88,"English","# Announcements\n# Main Categories of Data Models\n## Logical models\n## Conceptual models\n# Entity-Relationship Model Diagrams\n## Entities and entity sets\n## Attributes and primary keys\n# Entity Sets Examples\n# Relationships and Relationship Sets","[{\"question\":\"What is the difference between logical models and conceptual models in DBMS data modeling?\",\"answer\":\"Logical models describe, organize, and access data in a DBMS, and are independent of physical data structures. Conceptual models represent data independently from a specific DBMS, emphasizing semantics of real-world entities, attributes, and relationships.\"},{\"question\":\"How are entities, entity sets, and attributes represented in ER diagrams?\",\"answer\":\"An entity set is represented as a rectangle, and attributes are shown as ovals. Primary key attributes are indicated by underlining.\"},{\"question\":\"What is a relationship set, and how is its value interpreted?\",\"answer\":\"A relationship set connects two or more entity sets, represented by diamonds. Its value can be thought of like a table with one column per connected entity set and one row per connected combination of entities.\"}]","CS34800 Information Systems - Entity-Relationship Model - Lecture Notes | PDF",1792966191,222]