Question

I have a many to many relation between two tables in my database (MySql) :

• Category (id, name, id_parent)
• Sound (id, name)

A category can have 1 parent category, so a category can have many children. If a category has at least one child, it has no sounds in it. I do not allow sounds and children categories together.

So for a parent category, i want to get all children that may have children that may have children (…) and i want to count sounds in all children recursively.

Exemple :

Cat -> (CCat1 -> CCCat11(2 sounds), CCat2 (5 sounds), CCat3 -> CCat31 -> CCCat311 -> (CCCCat3111 (10 sounds), CCCCat3111 (1 sound))

There is no deep limit, that’s why i need a “recursively” way to count sounds.

• Cat has 3 children.
• CCat1 has 1 child.
• CCat2 has no child.
• CCat3 has 1 child that has 1 child that has 2 children.

Cat.nbSounds = 18

Answer 1

After more researches it seems that we can’t do what i want.

So i created a recursive method that retrieve children and calculate the number of sounds in each category (i count sounds in the category or i count categories children number of sounds).

If you find a magical way to do it anyway with linq to entities, i take it !