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The model is composed of entities, attributes, and relationships, including key attributes and cardinality types (one-to-one, one-to-many, and many-to-many) to specify how occurrences relate.",{"@graph":14,"@context":73},[15,34,56],{"@type":16,"itemListElement":17},"BreadcrumbList",[18,23,27,31],{"item":19,"name":20,"@type":21,"position":22},"https://docshare.wps.com","Home","ListItem",1,{"item":24,"name":25,"@type":21,"position":26},"https://docshare.wps.com/document/","Document",2,{"item":28,"name":29,"@type":21,"position":30},"https://docshare.wps.com/document/technology/","Technology",3,{"item":32,"name":10,"@type":21,"position":33},"https://docshare.wps.com/document/entity-relationship-model-erd-basics/656095/",4,{"url":32,"name":10,"@type":35,"image":36,"author":41,"headline":10,"publisher":44,"fileFormat":47,"inLanguage":8,"description":12,"dateModified":48,"datePublished":49,"encodingFormat":47,"isAccessibleForFree":50,"interactionStatistic":51},"DigitalDocument",{"url":37,"@type":38,"width":39,"height":40},"https://docshare.wps.com/thumbnails/entity-relationship-model-erd-basics/656095.png","ImageObject",300,407,{"name":42,"@type":43},"Dusta123","Person",{"url":19,"name":45,"@type":46},"DocShare","Organization","application/pdf","2026-10-30","2026-10-25",true,{"@type":52,"interactionType":53,"userInteractionCount":55},"InteractionCounter",{"@type":54},"ViewAction",6,{"@type":57,"mainEntity":58},"FAQPage",[59,65,69],{"name":60,"@type":61,"acceptedAnswer":62},"What is an Entity-Relationship model used for?","Question",{"text":63,"@type":64},"An ER model is used to represent entities and their relationships, helping design the logical structure of databases for storing, retrieving, and reporting business data.","Answer",{"name":66,"@type":61,"acceptedAnswer":67},"What are the main components of an ER diagram?",{"text":68,"@type":64},"An ER diagram has three components: entities, attributes, and relationships.",{"name":70,"@type":61,"acceptedAnswer":71},"What does cardinality define in an ER diagram?",{"text":72,"@type":64},"Cardinality defines the relationship between entities in terms of how many occurrences are involved, such as one-to-one, one-to-many, or many-to-many.","https://schema.org",{"og:url":32,"og:type":75,"og:title":10,"og:site_name":45,"og:description":12},"article",{"robots":77,"canonical":32},"index,follow",{"doc_id":79,"site_id":7},656095,1793052094,{"code":4,"msg":82,"data":83},"success",[84,88,92,96,101,104,109,114,119,122,126],{"id":22,"doc_module":4,"doc_module_name":25,"category_name":85,"show_sort_weight":86,"slug":87},"Story & Novel",90,"story-novel",{"id":26,"doc_module":4,"doc_module_name":25,"category_name":89,"show_sort_weight":90,"slug":91},"Literature",80,"literature",{"id":33,"doc_module":4,"doc_module_name":25,"category_name":93,"show_sort_weight":94,"slug":95},"Exam",70,"exam",{"id":97,"doc_module":4,"doc_module_name":25,"category_name":98,"show_sort_weight":99,"slug":100},5,"Comic",60,"comic",{"id":55,"doc_module":4,"doc_module_name":25,"category_name":29,"show_sort_weight":102,"slug":103},50,"technology",{"id":105,"doc_module":4,"doc_module_name":25,"category_name":106,"show_sort_weight":107,"slug":108},7,"Healthcare",40,"healthcare",{"id":110,"doc_module":4,"doc_module_name":25,"category_name":111,"show_sort_weight":112,"slug":113},8,"Research & Report",30,"research-report",{"id":115,"doc_module":4,"doc_module_name":25,"category_name":116,"show_sort_weight":117,"slug":118},9,"Religion & Spirituality",20,"religion-spirituality",{"id":117,"doc_module":4,"doc_module_name":25,"category_name":120,"show_sort_weight":117,"slug":121},"World Cup","world-cup",{"id":123,"doc_module":4,"doc_module_name":25,"category_name":124,"show_sort_weight":123,"slug":125},10,"Lifestyle","lifestyle",{"id":127,"doc_module":4,"doc_module_name":25,"category_name":128,"show_sort_weight":97,"slug":129},19,"General","general",{"code":4,"msg":82,"data":131},{"doc_id":79,"user_id":132,"nickname":42,"user_avatar":133,"doc_module":4,"category_id":55,"category_name":29,"doc_title":10,"doc_description":12,"doc_content":134,"file_id":135,"file_url":136,"file_type":137,"file_size":138,"view_count":55,"is_deleted":4,"is_public":22,"is_downloadable":22,"audit_status":22,"page_count":115,"language":139,"language_code":8,"site_id":7,"html_lang":8,"table_of_contents":140,"faqs":141,"seo_title":142,"seo_description":12,"update_tm":143,"read_time":144},962093541925,"https://ap-avatar.wpscdn.com/davatar_085a072bc5b1113ac321206ff7593b45","Topic: Entity-Relationship model  \nEntity-Relationship is a graphical representation of entities and their  \nrelationships to each other. Entity  \nRelationship Diagrams (ERDs) illustrate the logical structure of databases.  \nDiagrams created to design these entities and relationships are called entity  \nrelationship diagrams or ER diagram  \nUses of entity relationship diagram  \nEntity relationship diagrams are used to: 1. Identify the data that must be  \ncaptured, stored and retrieved in order to support the business activities  \nperformed by an organization; and  \n2. Identify the data required to derive and report on the performance  \nmeasures that  \nan organisation should be monitoring  \nComponents of Entity-Relationship Entity  \nRelationship diagrams have three different components:  \n1. Entities  \n2. Attributes  \n3. Relationships  \nEntities: Entities are objects or concepts within the data model. Each entity  \nis represented by a box within the ERD. Entities are abstract concepts, each  \nrepresenting one or more instances of the concept in question. An entity  \nmight be considered a container that holds all of the instances of a particular  \nthing in a system. Entities are equivalent to database tables  \nin a relational database, with each row of the table representing an instance  \nof that entity.  \nRemember that each entity represents a container for instances of the thing  \nin question. The diagram below has an entity for \"student\" and another for  \n\"school.\" This indicates that the system being modelled may contain one or  \nmore students and one or more schools.  \nSTUDENT  \nelements): These are the smallest  \nSCHOOL  \nAttributes (Data  \nunits of data that  \ncan be described in a meaningful manner. Entities are further described by  \ntheir attributes (sometimes called data elements) . For  \nexample, an EMPLOYEE entity may have the following Attributes:  \nEMPLOYEE  \nEmployee ID  \nSurname  \nFirstName  \nDate of Birth  \nTelephone  \nAddress  \nKey Attribute: A key attribute is the unique , distinguishing characteristic of  \nthe entity. For example, a student identification number might be the student’s  \nattribute.  \nRelationship  \nA relationship is an association among the instances of one or more entity  \ntypes that is of interest to the organization. A relationship is the association  \nbetween entities or entity occurrences. Frequently, a meaningful relationship  \nexists between two different types of entity. For example:  \n1. EMPLOYEEs work in a DEPARTMENT  \n2. For example, a Teacher teaches Subjects  \n3. LAWYERs advise CLIENTs  \n4. EQUIPMENT is allocated to PROJECTs  \n5. TRUCK is a type of VEHICLE  \nCardinality  \nThe cardinality/defines the relationship between the entities in terms of  \nnumbers. An entity may be optional: for example, a sales representative  \ncould have no customers or could have one or many customers.  \nTypes of cardinality relationship  \nThere are potentially three types of relationship can exist between two  \ndifferent entities:  \n1 . One-to-One Relationships  \n2. One-to-Many Relationships 3. Many-to-Many  \nRelationships  \nOne-to-One Relationships: This type of relationship  \ntakes place when a single occurrence of a second  \nentity. For example, a ROOF covers one BUILDING;  \nPatient to a doctor  \nOne-to-Many Relationships  \nThis type of relationship takes place when a single or One occurrence of  \nan entity is related to many occurrences of a second entity.  \nFor example, An EMPLOYEE works in one  \nDEPARTMENT; a DEPARTMENT has many EMPLOYEEs. A teacher to  \nmany students, pastor to members etc.  \nMany-to-Many Relationships  \nThis type of relationship takes place when many occurrences of an entity  \nare related to many occurrences of a second entity. For example,  \nEQUIPMENT is allocated to many Projects; A PROJECT is allocated many  \nitems of EQUIPMENT.","cbCaitsVNYqJeLzs","https://ap.wps.com/l/cbCaitsVNYqJeLzs","pdf",189880,"English","# Entity-Relationship Model\n## Uses of ER Diagrams\n## Components: Entities, Attributes, Relationships\n## Cardinality Types","[{\"question\":\"What is an Entity-Relationship model used for?\",\"answer\":\"An ER model is used to represent entities and their relationships, helping design the logical structure of databases for storing, retrieving, and reporting business data.\"},{\"question\":\"What are the main components of an ER diagram?\",\"answer\":\"An ER diagram has three components: entities, attributes, and relationships.\"},{\"question\":\"What does cardinality define in an ER diagram?\",\"answer\":\"Cardinality defines the relationship between entities in terms of how many occurrences are involved, such as one-to-one, one-to-many, or many-to-many.\"}]","Entity-Relationship Model - ERD Basics | PDF",1792966306,23]