{"id":3303,"date":"2023-02-27T15:13:07","date_gmt":"2023-02-27T20:13:07","guid":{"rendered":"https:\/\/community.mis.temple.edu\/mis2101sec730spring2023\/?p=3303"},"modified":"2023-02-27T15:14:09","modified_gmt":"2023-02-27T20:14:09","slug":"basics-of-entity-relationship-diagrams-2a","status":"publish","type":"post","link":"https:\/\/community.mis.temple.edu\/mis2101sec730spring2023\/2023\/02\/27\/basics-of-entity-relationship-diagrams-2a\/","title":{"rendered":"Basics of Entity Relationship Diagrams (2a)"},"content":{"rendered":"

\"Chen's
Chen’s Notation<\/figcaption><\/figure>
\"\"
Crow’s Notation<\/figcaption><\/figure><\/p>\n

ERD stands for Entity Relationship Diagram, and is typically used for database design to visualize the relationship between entities (people, things, concepts, etc.).
\nThe two notations for ERDs are
\n1. Chen\u2019s
\n2. Crow\u2019s Foot<\/p>\n

Chen\u2019s notation \u2013 The Chen ERD is the traditional method of creating ERDs. Unlike Crow\u2019s feet, all the entities are represented by different symbols and connected by the same connection notation. While cardinality notations may vary based on the design, the basic symbols and how they are all connected stay relatively the same.<\/p>\n

Crow\u2019s Foot notation \u2013 Similarly to Chen\u2019s, Crow\u2019s Foot serves the purpose to also illustrate entities and their relationships. However, the way in which relationships are connected depends to cardinality and which is the parent entity. For example, when connecting a child entity that only has one parent entity, there will be a small circle at the opposite end of the connecting line from the child. Relationships can have cardinalities of one-to-one, one-to-many, or many-to-many. The illustration of the connecting line will tell the viewer how entities are connected and from what angle.
\nI think this resource does a really great job of listing the different notations of each ERD since there are quite a few symbols to remember, especially for Crow\u2019s Foot. (https:\/\/www.conceptdraw.com\/How-To-Guide\/notation-symbols-for-erd#:~:text=There%20are%20used%202%20types,notations%3A%20Chen%20and%20Crow’s%20Foot<\/a>. )
\nAlthough Crow\u2019s Foot notation has more symbols to memorize and remember, I personally find it more organized than Chen\u2019s notation because there are less entities to look at. If you know the Crow Foot notation key, it is easy to visualize the data as well as quickly find pieces of information.<\/p>\n","protected":false},"excerpt":{"rendered":"

ERD stands for Entity Relationship Diagram, and is typically used for database design to visualize the relationship between entities (people, things, concepts, etc.). The two notations for ERDs are 1. Chen\u2019s 2. Crow\u2019s Foot Chen\u2019s notation \u2013 The Chen ERD is the traditional method of creating ERDs. Unlike Crow\u2019s feet, all the entities are represented […]<\/p>\n","protected":false},"author":29444,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_genesis_hide_title":false,"_genesis_hide_breadcrumbs":false,"_genesis_hide_singular_image":false,"_genesis_hide_footer_widgets":false,"_genesis_custom_body_class":"","_genesis_custom_post_class":"","_genesis_layout":"","footnotes":""},"categories":[663943],"tags":[],"class_list":{"0":"post-3303","1":"post","2":"type-post","3":"status-publish","4":"format-standard","6":"category-instructor","7":"entry"},"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/community.mis.temple.edu\/mis2101sec730spring2023\/wp-json\/wp\/v2\/posts\/3303","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/community.mis.temple.edu\/mis2101sec730spring2023\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/community.mis.temple.edu\/mis2101sec730spring2023\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/community.mis.temple.edu\/mis2101sec730spring2023\/wp-json\/wp\/v2\/users\/29444"}],"replies":[{"embeddable":true,"href":"https:\/\/community.mis.temple.edu\/mis2101sec730spring2023\/wp-json\/wp\/v2\/comments?post=3303"}],"version-history":[{"count":3,"href":"https:\/\/community.mis.temple.edu\/mis2101sec730spring2023\/wp-json\/wp\/v2\/posts\/3303\/revisions"}],"predecessor-version":[{"id":3308,"href":"https:\/\/community.mis.temple.edu\/mis2101sec730spring2023\/wp-json\/wp\/v2\/posts\/3303\/revisions\/3308"}],"wp:attachment":[{"href":"https:\/\/community.mis.temple.edu\/mis2101sec730spring2023\/wp-json\/wp\/v2\/media?parent=3303"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/community.mis.temple.edu\/mis2101sec730spring2023\/wp-json\/wp\/v2\/categories?post=3303"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/community.mis.temple.edu\/mis2101sec730spring2023\/wp-json\/wp\/v2\/tags?post=3303"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}