How relationship works in coreData
Leo
I know how to create a relationship in coredata,but i do not know how it works.
Eg.:
Employee: name id
Department: name
I can create a relationship(one to many) between 'Department' and 'Employee',and when i fetch 'Department', i will also get employees automatically.
If no relationship,I will create a field(employeeId) in department, and join 'Employee' table.
I do not know coredata how to get the correct employees by relationship.
Thanks
Leo
You can explore what is the entity is from the real sqlite file.
For example I have this relationship 
When I add three record,I use SliteBrowser to View the SQLite file It have five tables 
The ZDEPARTMENT Table 
The ZEMPLOYEE Table 
Note what I selected in ZEMPLOYEE,it save the id of department in ZDEPARTMENT,so it is quite clear how core data relationship works.
NOTE:
- Z_PK is the unique in SQLite Table
- Z_ENT is their entity id same as the one listed in the Z_PRIMARYKEY table
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