Question

I’ve got 5 tables. The main tables are: RisCtx, RisObj, and Ris.

RisCtx *———–* RisObj
RisObj *———–* Ris

(*—* = many-to-many)

So I got 2 more tables called: RisCtxRisObj and RisObjRis (for the many-to-many).

What I want is to create a view that collects all records from RisCtx which have a connection to Ris trough RisObj.

I’ve got kinda no clue :(.. I read something about INNER JOINs but I don’t see a bit clearance…

The schema

CREATE VIEW `mydb`.`CtxView_CtxFromObj_ObjFromRisk` AS
select RisCtx.*  
from RisCtx  
inner join RisCtxRisObj on RisCtx.id=RisObjRisCtx.RisCtx_id
inner join RisObj  on RisObjRisCtx.RisObj_id=RisObj.id 
inner join RisObjRis on RisObj.id=RisObjRis.Objective_id 
inner join Ris on RisObjRis.Risk_id=Ris.id 

Answer 1

Since you haven’t provided a schema, I can’t show you what your ON clauses should look like, but the basic query structure is:

select RisCtx.*
from RisCtx 
inner join RisCtxRisObj on ...
inner join RisObj  on ...
inner join RisObjRis on ...
inner join Ris on ...