How do I store information about a many-to-many relationship without the concept of a join table in Firebase? -


my firebase app contains many-to-many relationship between groups , users. i'd store information when user joined group - how go without concept of join table?

i'm using firebase example reference: https://examples-k9xbyc0bhfwtlkdgfhs.firebaseio-demo.com/

do recommend doing this?

app: {   groups: {     group1: {       members: {         user1: {           joindate: '2016-01-22t02:43:27.817z',           iscreator: true         },         user2: {           joindate: '2016-01-23t02:43:27.817z',           iscreator: false         }       }     }   },   users: {     user1: {       firstname: 'adam',       lastname: 'soffer',       groups: {         group1: {           joindate: '2016-01-22t02:43:27.817z',           iscreator: true         }       }     },     user2: {       firstname: 'joe',       lastname: 'shmoe',       groups: {         group1: {           joindate: '2016-01-23t02:43:27.817z',           iscreator: false         }       }     }   } }

the official structuring data guide great resource helping conceptual design this.

in general, it's best use nested data sparingly , flatten data possible.

you can represent same characteristics flatter structures.

membership: {   user1: {     group1: { joined: '2016-01-23t02:43:27.817z' },     group2: { joined: '2016-01-23t02:43:27.817z' }   } },  groups: {   group1: {     creator: user1   },   group2: {     creator: user1   } },  users: {   user1: {     firstname: 'adam',     lastname: 'soffer'   } }

we've used membership object manage many-to-many relationship of users , groups, allowing remove lot of nesting in groups , users fields.

assuming each group has 1 creator, it's possible move group objects, giving guarantee there can 1 creator , removing denormalized data our user objects.


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