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Oracle SQL

Instructions:

Answer 50 questions in 15 minutes.
If you are not ready to take this test, you can study here.
Match each statement with the correct term.
Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.

This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.

1. Explain in detail the impact of INDEXES and how they are used by Oracle.
ROLLBACK
KEEP INDEX
When you want to run the same script repeatedly - but want to be able to change a variable you would use a substitution variable. During the execution of the script the user will be prompted to input the variable to use.
To achieve good performance for data retrieval and data manipulation statements Oracle uses indexes. In the same way you would use an index in the back of a book to quickly find information - Oracle uses indexes to speed up data retrieval. If the app

2. To restart a sequence at a lower number - you can drop and ________ the sequence.
Re-create
ANY
IN ANY ALL SOME
Surrogate

3. Instead of using the Oracle Outer Join Operator or the ANSI syntax - you can achieve the same result with two SQL statements: ____________ and a ____________
FALSE
Equijoin and correlated subquery
Scalar
BETWEEN

4. The ROWID pseudocolumn is not an ________- but it acts like one.
VALUES
Surrogate key
Actual column
ROLLBACK

5. The NEXTVAL and CURRVAL pseudocolumns can be used in which of the following SQL constructs? Select all that apply.
All
VALUES clause of an INSERT statement
Lists all objects accessible for the chosen database connection. Also lists a helpful dependencies report for accessing change impact.
INNER JOIN

6. In a view you can give a column a different name than it has in the...
Structured Query Language
Scale
Parent table
DESC dict;

7. The term ____________ ___________ is used to express a join that satisfies the join condition.
X
Multiple rows
Same
INNER JOIN

8. When using the following data: NUMBER(10 -4) - the # 4 is called the __________.
Subqueries allow you to nest multiple queries into each other. This gives you the ability to use one statement to break down a problem into individual components. Without nesting queries - you would be required to have multiple queries which could be
Correlated
Scale
Committed

9. The time zone displacement value indicates the time difference from _______.
UTC
The indexed column is part of an expression. In this case - consider creating a function-based index instead
Combine
Equijoin

10. The same function can be used ______ in a SELECT statement.
X
Re-create
ANSI
Twice

11. You can simplify the writing of SQL statements by writing SQL _________ that generate and execute other SQL statements.
Retrieve
When the table is small (unless your business rules require you too)
A correct statement
Script

12. SQL*Plus is used more than SQL Developer when you need to...
Default is 14; when you use the default - you repeat the heading every 14 rows.
Run scripts
Hide data
Extra spaces

13. How many characters can be stored in the CHAR column/field?
Any
User-defined reports
2000
UNION

14. Explain how Substitution Variables are used when writing scripts.
When you want to run the same script repeatedly - but want to be able to change a variable you would use a substitution variable. During the execution of the script the user will be prompted to input the variable to use.
The indexed column is part of an expression. In this case - consider creating a function-based index instead
Any
All

15. Explicit data type conversion is preferable to Oracle's...
VALUES
Combine
Implicit conversion
Twice

16. Oracle uses the outer join operator to indicate that nulls are shown for...
Dynamic SQL is used to be continuously updated by the background processes in the Oracle instance but never by the user.
Nested
Non-matching rows
SELECT SYSDATE+1/96 - FROM dual

17. Queries that are found in parentheses are done first - just as in the order of operations when doing...
V$
SYSDATE
MODIFY
Mathematical equations

18. What is the keyboard shortcut for the ROLLBACK command?
SELECT SYSDATE+1/96 - FROM dual
Run scripts
F12
DROP INDEX need_to_pass_i

19. The key that most database designers prefer and is chosen by the system is the _____________ key.
Surrogate
Asterisk
Business problems
Same

20. _________ rows are not allowed in the relational model.
Orphan
Any
ADD
USER_ - ALL_ - DBA_ - and V$

21. NUMBER functions can be...
Lists all objects accessible for the chosen database connection. Also lists a helpful dependencies report for accessing change impact.
LIKE
Nested
Default is 14; when you use the default - you repeat the heading every 14 rows.

22. Explain why constraints are used when building tables.

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23. What is the name of the view where you can find the collection of static and data dictionary tables and views - along with their descriptions?
Committed
ANSI
ALL_OBJECTS
DICTIONARY

24. Explain how the SPOOL command is used and what program it can be used in.
Actual column
Business problems
Any
The SPOOL command - together with a file name - spools any subsequently issued SQL Plus or SQL command to a file. Just as with other file names - you can add a path to store the file in a directory other than your SQL Plus default directory. SQL Deve

25. It is always good practice to include the old values in the WHERE clause of UPDATE to ensure that another session or user _________________ in the meantime.
When you issue a INSERT - UPDATE - DELETE - or MERGE statement - Oracle automatically locks the modified rows. The lock prevents other sessions from making changes to these rows. The lock is released when the session initiating change commits or roll
Has not changed the name
The main components of a ROWID are the data object number - the number of the data block - the numbers of rows within the data block - and the data file number.
Multiple rows

26. How many characters can you have using the VARCHAR data type?
4000
LIKE
Location of the file
Rounded edges

27. The TIMESTAMP WITH LOCAL TIME ZONE data type allows...
@ or START
Fractional seconds
SELECT SYSDATE+1/96 - FROM dual
99.99

28. The _______ function adds values together for a group of rows.
Any
SUM
User-defined reports
X

29. Returns rows if the condition is true for all the values in the list
Default is 14; when you use the default - you repeat the heading every 14 rows.
Mathematical equations
All
Details

30. When you have issued a DELETE command - you can still ________ those rows and restore the information.
Retrieve
V$
X
When you issue a INSERT - UPDATE - DELETE - or MERGE statement - Oracle automatically locks the modified rows. The lock prevents other sessions from making changes to these rows. The lock is released when the session initiating change commits or roll

31. All SQL statements contained within a script must end with a _______________ - even if they are done in SQL Developer.
Semicolon or forward slash
RIGHT LEFT JOIN
Non-matching rows
Structured Query Language

32. An outer join includes the result rows returned by an __________ plus extra rows where no matches are found.
ANY
Combine
Equijoin
Constraints are used to enforce the business rules of a system. For instance - 'The salary of an employee may not be a negative number' may be enforced with a check constraint on the salary column. Constraints also ensure integrity and data consisten

33. What is the data type you can use if you need an unlimited number of textual characters?
Any
ANY
CLOB
ON

34. What is the name of the key automatically generated from a sequence?
Surrogate key
NATURAL JOIN
Load the file into the SQL Statement Box - by opening the location the file is stored and inserting it into the statement Box. Next you can press the F5 key.
All caps

35. The query retrieves more than 5 to 15 percent of the rows
The indexed column is part of an expression. In this case - consider creating a function-based index instead
Both MIN and MAX
DESC dict;
To achieve good performance for data retrieval and data manipulation statements Oracle uses indexes. In the same way you would use an index in the back of a book to quickly find information - Oracle uses indexes to speed up data retrieval. If the app

36. When column names on the tables are different - you use the ______ condition.
SELECT DISTINCT menu FROM restaurant
ON
DICTIONARY
Surrogate key

37. UNION ALL does not sort - therefore it is less time consuming to use than the...
Results
Orphan
UNION operator
Recursive

38. A _____ is a query definition stored in the database that looks just like a table - but does not have any physical rows
Columns
X
Common column value
Control - Revoke - Define - TRUNCATE Manipulate - MERGE

39. The ____________ command makes changes permanent.
COMMIT
999999.9999
Rounded edges
4000

40. __________________ inserts the current date and time.
CLOB
Multiple rows
SYSDATE
To achieve good performance for data retrieval and data manipulation statements Oracle uses indexes. In the same way you would use an index in the back of a book to quickly find information - Oracle uses indexes to speed up data retrieval. If the app

41. To revert back to a state that happened before you ran your change statement - you issue a ____________ command.
SELECT SYSDATE+1/96 - FROM dual
F12
ROLLBACK
All

42. The data type definitions NUMBER(10) and NUMBER(10 -0) are the...
Fractional seconds
Same
Retrieve
RIGHT LEFT JOIN

43. Explain Flashback queries and how they are used. Give an example of a FLASHBACK_TRANSACTION query and explain what it does row by row.

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44. SELECT * FROM instructor ORDER BY phone
CLOB
The way NULL values are treated
INNER JOIN
A correct statement

45. The ______ depicts the M of a 1:M relationship.

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46. When you INSERT new information into a table - it is followed with a _______ keyword that contains the information that is going to be added to the table.
VALUES
Semicolon or forward slash
DESC dict;
**** Select a row from the outer query - Determine the value of the correlated column - Execute the inner query for each record of the outer query. - Feed the results of the inner query to the outer query and evaluate it. It if satisfies the criteria

47. What is Oracle's most popular index storage structure?
TO_CHAR function
4
B-Tree Index
Running a script file

48. What is the syntax used to indicate that you are using the Oracle Outer Join operator?
SUM
+
Command returns the number of records returned by a query.
Re-create

49. Subqueries can return...
X
Default is 14; when you use the default - you repeat the heading every 14 rows.
Orphan
Multiple rows

50. Explain how Oracle treats locks when a database is being updated and needs to be viewed by other users.
Scale
When you issue a INSERT - UPDATE - DELETE - or MERGE statement - Oracle automatically locks the modified rows. The lock prevents other sessions from making changes to these rows. The lock is released when the session initiating change commits or roll
SUM
USER_ - ALL_ - DBA_ - and V$