wht is d/f b/w inner join and outer join ? d/f group by and order by having by ?
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Answer / srinivasa yadav
INNER JOIN: ALL THE MATCHED ROWS FROM BOTH THE TABLES ARE
DISPLAYED IN THE RESULTANT TABLE.
OUTER JOIN: THERE ARE THREE TYPES OF OUTER JOIN
1)LEFT OUTER JOIN
2)RIGHT OUTER JOIN
3)FULL OUTER JOIN
LEFT OUTER JOIN:- ALL THE MATCHED AND UNMATCHED ROWS FROM
BOTH TABLES FROM THE LEFT TABLE ARE DISPLAYED IN THE
RIGHT OUTER JOIN:- ALL THE MATCHED AND UNMATCHED ROWS FROM
BOTH RIGHT TABLE ARE DISPLAYED IN THE RESULTANT TABLE.
FULL OUTER JOIN:- ALL THE MATCHED AND UNMATCHED ROWS FROM
BOTH THE TABLES ARE DISPLAYED IN THE RESULTANT TABLE.
GROUP BY CLAUSE:- IT IS USED ON GROUP OF DATA AND PROCESS AN
ORDER BY:- IT IS USED TO SORT THE DATA IN ASCENDING OR
EX:- SELECT EMPID FROM EMP_TBL ORDER BY
DSC (OR) ORDER BY 1.
ORDER BY 1 i.e THE COLUMN NUMBER (EMPID)
HAVING BY:- IT IS USED FOR CONDITION CHECKING.
|Is This Answer Correct ?||5 Yes||1 No|
Answer / lu
u have 2 table (a,b), u join together,u get colunms
matching it's called inner....
u have 2 tables (a,b), u select a colunm(b) doesn't exist
in a...it's called outer...
goup by using for a row...
having by using for column
|Is This Answer Correct ?||2 Yes||0 No|
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