Hey guys, I'm having an issue understanding how to write a table that uses an id and another id which both have dual keys. What I mean by dual keys is they use primary key and foreign keys.
Example:
Table Name = Enrollment
Column Name = Sid, Csecid, Grade
Data Type = NUMBER, NUMBER, NUMBER
Lgth = w/e,w/e,w/e
PK = Sid, Csecid
FK = Sid, Csecid
Check = A,B,C,D,F,I
I'm having issues writing it out in SQL code such as Create Table Enrollment... etc
Jump to PostJust refer to the standard EMP and DEPT tables of SCOTT schema.
Try to analyze that , you will be able to write your own.
Just refer to the standard EMP and DEPT tables of SCOTT schema.
Try to analyze that , you will be able to write your own.
Primary Keys SHOULD be a single column with unique values.
Foreign Keys SHOULD be a single column refering to Primary Keys.
If you want uniqueness of multiple columns (in a single record), create a Unique Key.
Keep it simple!
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