0

databases Online Quiz - 40

Description: databases Online Quiz - 40
Number of Questions: 20
Created by:
Tags: databases
Attempted 0/20 Correct 0 Score 0

How many columns are presented after executing this query: SELECT address1||','||address2||','||address2 "Adress" FROM employee;

  1. 3

  2. 4

  3. 1

  4. None


Correct Option: C
  1. Column

  2. 1966_Invoices

  3. #Invoices

  4. Catch_#22


Correct Option: D
  1. Default tablespace for the user

  2. Oracle will give an error

  3. System tablespace

  4. Users tablespace


Correct Option: A
  1. cursor CAPITALS is

  2. select CITY, STATE

  3. into my_city, my_state

  4. from CITIES where CAPITAL = 'Y';


Correct Option: C

PL/SQL raises an exception, in which TWO of the following cases:

  1. When the datatypes of SELECT clause and INTO clause do not match

  2. When a SELECT statement returns more than one row

  3. When a SELECT statement returns no rows

  4. When INTO statement is missing in the SELECT statement


Correct Option: B,C

Assuming today is Monday, 10 July 2000, what is returned by this statement: SELECT to_char(NEXT_DAY(sysdate, 'MONDAY'), 'DD-MON-RR') FROM dual;

  1. 10-JUL-00

  2. 17-JUL-00

  3. 12-JUL-00

  4. 11-JUL-00


Correct Option: B
  1. No. of rows returned by SQL statement are HIGH

  2. No. of rows returned by SQL statement are FEW

  3. No. of rows returned by SQL statement are > 10000

  4. No. of rows returned by SQL statement are > 50000


Correct Option: B

Why one should not use “select * from table;” Choose all that apply

  1. Avoid full table scan

  2. Avoid index scan

  3. Avoid network traffic

  4. Avoid cartesian join


Correct Option: A,C
  1. Columns that contains values with less variation in the number of duplicates

  2. Columns that contains values with large variation in the number of duplicates

  3. Columns that contains values with no variation in the number of duplicates

  4. Columns that contains values with ZERO variation in the number of duplicates


Correct Option: B

Which tool is used to analyze access path of SQL statement?

  1. Exp

  2. Imp

  3. Explain Plan

  4. vi Editor


Correct Option: C
  1. The more heavily indented an access path is, the earlier it is executed

  2. The more heavily indented an access path is, the later it is executed

  3. If two steps are indented at the same level, the uppermost statement is executed first

  4. If two steps are indented at the same level, the uppermost statement is executed last


Correct Option: A,C
  1. Right to Left processing of Source (Tables, views etc.) by Parser

  2. Left to Right processing of Source (Tables, views etc.) by Parser

  3. Bottom to Up processing of WHERE condition clauses

  4. Up to Bottom processing of WHERE condition clauses


Correct Option: A,C

Why one should not use NULL / NOT NULL operator on indexed columns?

  1. Using NULL / NOT NULL on indexed columns won’t use INDEX

  2. Using NULL / NOT NULL on indexed columns gives ERROR

  3. Using NULL / NOT NULL on indexed columns disables INDEX

  4. Using NULL / NOT NULL on indexed columns makes the INDEX unusable


Correct Option: A
  1. Automated Database Deployment Monitor

  2. Automated Database Development Monitor

  3. Automated Database Diagnostic Monitor

  4. Automated Database Distributed Monitor


Correct Option: C
  1. V$SQL

  2. V$SQL_STAT

  3. V$SQLSTATS

  4. V$SQL_STATISTICS


Correct Option: C

Which of the following degrades the performance of database?

  1. Equi Join

  2. Outer Join

  3. Non-Equi Join

  4. Cartesian Join


Correct Option: D
- Hide questions