Crows-foot notation in an Sqlite database model -


i'm getting grips using 'crows-foot' notation design sqlite databases using navicat. in book chapter designed users , running software have come across following example, consisting of er diagram , explanatory text:

there many-to-one relationship between category table , task table. in our case, task can have 1 category associated it, category can have many tasks under it. such, task can assigned 1 user, user can have many tasks. enter image description here

i surprised read because notation seems @ odds description. way of reading these diagrams (arrived @ examining various freely available examples on internet) start table (say task) @ notation 'attached' related table (in case 'one or more') , construct relationship follows: task belongs 'one or more' categories. such relationship possible of course, seems inconsistent verbal description of desired relationship, namely: 'a task can have 1 category associated it'. misunderstanding crow's-foot notation?

in erd (whether using crow's foot or chen notation) "many" side has foreign key, task table has foreign key category_id , therefore on "many" side while category has related primary key named id , therefore on "one" side. so, you're right in interpretation actually.


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