Hi Ranger,
You are may be familiar with SQL tables. CRM relationships are similar to how we create relationship in SQL between two tables.
In SQL,
1. For 1:N or N:1 Relationship -
The 1:N relationship is defined as a relationship between two tables where a row from one table can have multiple matching rows in another table. This relationship can be created using Primary key-Foreign key relationship.
For ex., there are two tables in SQL
1) Country
2) States
Between Country and States table there is 1:N relationship, so one Country can have multiple States. In States table “countryid” is a foreign key which is a primary key of Country table.
2. For N:N Relationship -
In a N:N relationship, a row in table A can have many matching rows in table B, and vice versa. The N:N relationship could be thought of as two one-to-many relationships, linked by an intermediary table. The N:N relationship is used when you are in the situation where the rows in the first table can map to multiple rows in the second table and those rows in the second table can also map to multiple (different) rows in the first table.
For ex., We have two tables,
1). Teacher
2). Classes
Between Teacher and Classes table there is N:N relationship, so one teacher can be assigned to many classes and one class can be assigned to many teachers.
In Dynamics 365, We use Entity as a table.
1) 1:N or N:1 Relationship -
An entity relationship where one entity record for the Primary Entity can be associated to many other Related Entity records because of a lookup field on the related entity. When viewing a primary entity record you can see a list of the related entity records that are associated with it.
Similarly we have same tables (Entity) (i.e. Country and States) in CRM also. So country (Primary entity) can have many related States associated with it.
2) N:N Relationship –
An entity relationship that depends on a Relationship Entity, called as Intersect entity, so that many records of one entity can be related to many records of another entity. When viewing records of either entity in a N:N relationship you can see list of any record of the other entity that are related to it.
Here we have same tables (Entity) (i.e. Teachers and Classes) in CRM also which have N:N relationship. So one teacher can be associated to many classes and one class can be associated to many teachers.
Hope this helps.
Thanks!
