topic Re: Primary Key Foreign Key Problem in Application Development and Automation Discussions

Primary Key Foreign Key Problem

Former Member — Fri, 09 Aug 2013 06:03:41 GMT

I have created three tables as per following,

1) Department

fields: dep_id(primary key),

dep_name

2)Faculty Table

fields: fac_id(primary key),

fac_name,

dep_id(foreign key)

3)Student Table

fields: std_id(primary key),

std_name,

std_add,

fac_id(foreign key),

dep_id(foreign key).

Now i want to make condition that fac_id and dep_id should be correspond in student table ,

for example ,

if i enter 1 as fac_id then it should automatically fetch it's dep_id from the fac_id..

Re: Primary Key Foreign Key Problem

former_member209120 — Fri, 09 Aug 2013 06:19:00 GMT

Hi Alex Hanes

See this link to create foreign key for table

http://www.saphub.com/abap-tutorial/how-to-create-a-foreign-key-in-sap-table/

Re: Primary Key Foreign Key Problem

FredericGirod — Fri, 09 Aug 2013 06:19:05 GMT

Hi Alex,

I'm not sure you could do this (easily) with SAP. Maybe if you build a logical database (with some Abap code). But SAP didn't use the "advanced tools" of Oracle because it could used several different database.

regards

Fred

Re: Primary Key Foreign Key Problem

Former Member — Fri, 09 Aug 2013 06:25:17 GMT

Thanks on your prompt reply to this.I am able to make it work with 2 tables.But, when i try it on 3 tables things get messy. It looses it's consistency.

Re: Primary Key Foreign Key Problem

Former Member — Fri, 09 Aug 2013 06:36:07 GMT

Hello,

As per my understanding there is no need to dep_id in student table , b'cz based on Student id you can get a Unique fac_id and Based on fac_id u can get unique Dept_id and Name, so remove

dep_id from student table.

Chandra..

Re: Primary Key Foreign Key Problem

Former Member — Fri, 09 Aug 2013 07:00:24 GMT

yeah that's right thanks dear.