Hi , I am posting some interview ques .
what is the use of cursors ? what is the diff between
select and cursor ? bith are used for data retrival ..
rite?
Answers were Sorted based on User's Feedback
Answer / yuvaevergreen
>>Cursors are memory structures used to handle multiple
rows at a time.
>>Though,select statement can fetch only multiple rows, we
cannot handle multiple rows using host variables.
Basic difference would be single row handling and multiple
rows handling.
Is This Answer Correct ? | 6 Yes | 0 No |
Answer / reddy
cursors are used to retrieve multiple rows . Cussors will
retrieve one row at a time and save the data in the
hostvariables.For retreiving the 2 nd row, we need to
repeat the loop.the same process is continued at the end of
data.
select stmt will retrieve multiple rows at a time. assume
that there are 10 rows in a table.
EX: EXEC SQL
SELECT empno , ename into :hvempno ,:hvename from emp;
END EXEC;
Here the above sql query reults all the 10 rows. But , the
host variables will hold only one row of data.the remaining
9 rows will not be stored any where.
hope this may help u
Is This Answer Correct ? | 4 Yes | 4 No |
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