Natural Join
Let there be two relations. This operator considers a pair of tuples one from each relation and combines when the common attribute values in both the tuples are the same.
Let us consider the following relations:
r1 : STUD r2 : DEPT ———————————- ————————————
SNo SName DNo DNo DName
———————————- ————————————
121 xyz 21 21 CSE
123 pqr 21 22 IT
126 mnp 22 23 ECE
128 abc 22 24 ME
130 jkl 23 25 EEE
Example 1 : Find the result of the following SQL command.
Select *
From STUD natural join DEPT;
Output :
DNo SNo SName DName
21 121 xyz CSE
21 123 pqr CSE
22 126 mnp IT
22 128 abc IT
23 130 jkl ECE
Example 2 : Find the result of the following SQL command.
Select *
From DEPT natural join FACULTY;
Output :
FNo D-No D-Name FName Qual
522 21 CSE MM Ph.D.
524 22 IT NN MTech
525 22 IT VV MTech
527 23 ECE PP MTech
530 23 ECE QQ MTech
533 24 ME RR Ph.D.
535 24 ME SS Ph.D.
537 25 EEE TT MTech
539 25 EEE WW MTech
Natural Join