How do I do a one-to-one relation ?
See original GitHub issueOr one-to-many - from the one side (for example a user has many PhoneNumber
’s. How do I define the Owner
of a PhoneNumber
object in the PhoneNumber
schema ?)
Issue Analytics
- State:
- Created 8 years ago
- Reactions:1
- Comments:5 (3 by maintainers)
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Top GitHub Comments
Here is the section from the docs on model definitions. I am still working on this and it isn’t yet ready to be put up but maybe it will help:
Models and Objects
Realm data models are defined by passed schema information into a Realm object during initializion. The schema for an object consists of the object’s
name
and a set of properties each of which has aname
,type
and optionaldefault
andoptional
designations. You can pass thename
from other object schema for the type to create links between objects, and Realm also supports lists of links to other objects.If you’d prefer your objects inherit from a prototype, you just need to define the schema on the prototype object and instead pass in the constructor when creating a realm:
Once you have defined your object models you can create and fetch objects from the realm
Basic Property Types
Realm supports the following basic types:
bool
,int
,float
,double
,string
,data
, anddate
.bool
properties are mapped to JavaScriptBoolean
objectsint
,float
, anddouble
properties map to JavaScriptNumber
objects. Internally ‘int’ and ‘double’ are stored as 64 bits whilefloat
is stored with 32 bits.string
properties map toString
data
properties map toArrayBuffeer
date
properties map toDate
Object Properties
For object types you must specify the underlying
objectType
for each property. For single object properties you can specify theobjectType
as the primary type as shorthand:When acessing object properties, you can access nested properties using normal property syntax:
List Properties
For list properties you must specify the property type as
list
as well as theobjectType
:When accessing list properties a
RealmArray
object is returned.RealmArray
has methods very similiar to a vanilla JavaScript array. The big difference is that any changes made to aRealmArray
are automatically persisted to the underlying Realm. AdditionalyRealmArray
s belong to the underlying object they were aquired from - you can only getRealmArray
instances by calling a property getting and cannot create them manually.Optional Properties
Properties can be declared as optional or non-optional by specifying the
optional
designator in your property definition:Default Property Values
Default property values can be specified by setting the
default
designator in the property definition. To use a default value leave the property unspecified during object creation.Primary Keys
You can specify the
primaryKey
property in an object model forstring
andint
properties. Declaring a primary key allows objects to be looked up and updated efficiently and enforces uniqueness for each value. Once an object with a primary key is added to a Realm, the primary key cannot be changed.@dorongutman the relations are saved as references in the database, but you will get a new JS object on every access that references the same underlying object in the database.