DBMS MCQ

DBMS


1.How many null values r allow in unique key column? Ans : Infinite
2. we cannot define constraints on-------database?? Ans: Lob
3. field value can be found at the intersection of:  Ans : a row and column
4. Which stemement is true
1;intersect doesnot ignore null values
2;reversing intersected tables doesnot alter result
Ans: Both
5. .............. values are not ignored during duplicate checking in UNION
Ans:NULL
6. Illegal symbol for table name?
$
#
!
_
Ans: !
7. Grant and revoke are discussed under? Ans:DCL
8. ................ is a synoym for USER_TABLES Ans : TABS
9. which of the following is not a set operator?
1 UNION
2 JOIN
3 MINUS
4 INTERSECT                  
Ans:Join
10. collection of objects under a user  Ans:Schema

11. which is not set operator??
          1  Union
          2 Intersect 
          3  Minus
         4 Join
Ans : Join
12. what does execute(sqlquery) method called on a statement object return
1)int
2)boolean
3)string
4)resultset
Ans:
13. constraint names and their corresponding column names can be listed from
a. USER_CONSTRAINTS
b. USER_OBJECTS
c. USERS_CONSTRAINTS
d. USER_CONS_COLUMNS
Ans:USER_CONS_COLUMNS
14. WHICH VALUES R NOT IGNORED DURING DUPLICATE CHECKING IN UNION
    1.NULL
   2.0
   3.STRING
   4.DATE
Ans:NULL
15. In Oracle 11g to compare 2 string values which of the following operations can be used
1.=
2.==
3.strcmp()
4.isequals...
Ans:Equals
16. Which symbol is used to specify a group of characters in SQL server database?
1.#
2.%
3.@...
4.^
Ans:%
17. oracle sql>> truncate is discussed under?1.dml,ddl,dcl,tcl?
Ans:DDL