Oracle Tutorials

(A) Set the new format in the DATE_FORMAT key in the windows Registry.
(B) Alter session to set NLS_DATE-FORMAT.
(C) Change the Config.ora File for the date base.
(D) Change the User Profile USER-DATE-FORMAT.

17. Which of the following is not necessarily an advantages of using a package rather than
independent stored procedure in data base.
(A) Better performance. (B) Optimized memory usage.
(C) Simplified Security implementation. (D) Encapsulation.

18. Integrity constrains are not checked at the time of
(A) DCL Statements. (B) DML Statements.
(C) DDL Statements. (D) It is checked all the above cases.

19. Roll Back segment is not used in case of a
(A) DCL Statements. (B) DML Statements. (C) DDL Statements. (D) all of the above.

QUERIES
Where do we use distinct keyword ? Distinct is used to avoid duplicating records..................... DELETE
FROM table_name A
WHERE rowid>(SELECT min(rowid) from table_name B where
B.table_no=A.table_no);

CREATE TABLE new_table AS SELECT DISTINCT * FROM old_table;

DROP old_table
RENAME new_table TO old_table
DELETE FROM table_name A
WHERE rowid NOT IN (SELECT MAX(ROWID) FROM table_name
GROUP BY column_name)

How you will avoid your query from using indexes ?
SELECT * FROM emp
Where emp_no+' '=12345;

i.e you have to concatenate the column name with
space within codes in the where condition.

SELECT /*+ FULL(a) */ ename, emp_no from emp
where emp_no=1234;