Re: Reasons for creating linking tables?
| От | Oliveiros d'Azevedo Cristina |
|---|---|
| Тема | Re: Reasons for creating linking tables? |
| Дата | |
| Msg-id | C62AEE3602814FBD8CACEA459839DD2D@marktestcr.marktest.pt обсуждение исходный текст |
| Ответ на | Reasons for creating linking tables? (Machiel Richards <machielr@rdc.co.za>) |
| Ответы |
Re: Reasons for creating linking tables?
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| Список | pgsql-novice |
I would like to get the point of view from you guys out there who has had a lot of database experience.
While busy looking into a database that have a lot of issues I have found the following scenario :
- Let's call the 3 tables in question tables a,b & c.
- Currently table a has got a FK referencing table b
- table b contains only 1 field called id which is the PK and also a FK referencing table c
- table c is once again a table with a couple of fields.
My question on this is, why create the linking table?
Surely the linking table can be removed and the data referenced directly between tables a & c?
Is there a specific reason why this would need to be done?
I would like to get the point of view from you guys out there who has had a lot of database experience.
While busy looking into a database that have a lot of issues I have found the following scenario :
- Let's call the 3 tables in question tables a,b & c.
- Currently table a has got a FK referencing table b
- table b contains only 1 field called id which is the PK and also a FK referencing table c
- table c is once again a table with a couple of fields.
My question on this is, why create the linking table?
Surely the linking table can be removed and the data referenced directly between tables a & c?
Is there a specific reason why this would need to be done?
* In this specific case, frankly, I can't see none...It seems you have a relation Many-to-One between table a and c.I usually place an associative table in the middle when I have a many-to-many relationship, which is not the case.
In this scenario I would consider table b superfluous (specially when it has no other fields except its ID) and short circuit it.That's my oppinionBest,Oliver
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