Test your basic knowledge |

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. What is the keyboard shortcut for the ROLLBACK command?
Default is 14; when you use the default - you repeat the heading every 14 rows.
Command determines the total number of characters SQL *Plus displays in on line before beginning a new line.
F12
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.

2. UNION ALL does not sort - therefore it is less time consuming to use than the...
Common column value
UNION operator
Logical unit of work
Nested

3. You can pass parameters from the operating system when ___________ in SQl*Plus
Running a script file
ADD
Extra spaces
Command returns the number of records returned by a query.

4. SQL*Plus is used more than SQL Developer when you need to...
Run scripts
User-defined reports
F12
Inconsistencies

5. To equijoin a table with another table involves matching the...
Committed
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.
Common column value
KEEP INDEX

6. Oracle uses the outer join operator to indicate that nulls are shown for...
Non-matching rows
Orable's flashback query feature allows you to look at values of a query at a specific time in the past - such as before specfic DML statements occured. This can be usefull in case a suer accidentally performs an unintended but committed DML change.
Three
IN ANY ALL SOME

7. When you run a script in SQL*Plus you must give the...
DICT_COLUMNS
The way NULL values are treated
RUN SCRIPT
Location of the file

8. To join four tables - you must have at least _____ join conditions.
Surrogate key
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.
Retrieve
Three

9. The time zone displacement value indicates the time difference from _______.
Twice
Structured Query Language
UTC
Logical unit of work

10. 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
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
Three
RUN SCRIPT

11. A _____ is a query definition stored in the database that looks just like a table - but does not have any physical rows
X
All caps
Default is 14; when you use the default - you repeat the heading every 14 rows.
Hide data

12. The ____________ command makes changes permanent.
Equijoin
All caps
Both MIN and MAX
COMMIT

13. Write a solution that adds 20 minutes to a given date.
SELECT SYSDATE+1/96 - FROM dual
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.
Non-matching rows
Command returns the number of records returned by a query.

14. In a view you can give a column a different name than it has in the...
Actual column
F12
Orphan
Parent table

15. A transaction is a...
Logical unit of work
Hide data
GROUP BY
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

16. When using the following data: NUMBER(10 -4) - the lowest number you can possibly have is __________.
DECODE
B-Tree Index
FALSE
999999.9999

17. 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
Hide data
99.99
X

18. The ______ operator compares a list of values for equivalency
Orable's flashback query feature allows you to look at values of a query at a specific time in the past - such as before specfic DML statements occured. This can be usefull in case a suer accidentally performs an unintended but committed DML change.
BETWEEN
ANY
Leading-edge

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

20. Returns rows if the condition is true for all the values in the list
Twice
X
All
ALL_OBJECTS

21. Explain in detail the impact of INDEXES and how they are used by Oracle.
Re-create
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
Business problems
Data

22. What is the tab in SQL Developer where data dictionary view information can be found?
RENAME just_two_more_weeks TO finally_i
Details
Results
BETWEEN

23. The ________________ is a type of statement whereby you retrieve data that exists in one table - but not in another.
The way NULL values are treated
COUNT(registration_date) - AVG (capacity) - MIN (capacity) - MAX (capacity)
MINUS
Data

24. The TRUNC function on a date without a format model truncates the timestamp to...
Has not changed the name
12:00:00 A.M
Running a script file
SUM

25. Users can only see changes made to a database once they have been...
Scale
RENAME - COPY - DROP - TRUNCATE - LOCK - & COMMENT
Committed
DESC dict;

26. Match each of the SQL commands on the left with a verb from the list.
ROLLBACK
Scale
Control - Revoke - Define - TRUNCATE Manipulate - MERGE
STORAGE

27. The ________ operator cannot compare against a list of values.
INNER JOIN
LIKE
SELECT SYSDATE+1/96 - FROM dual
Static or dynamic

28. When using the data NUMBER(10 -4) there will be _______ digits following the decimal point.
4
CLOB
B-Tree Index
Inconsistencies

29. The purpose of the HAVING clause is to eliminate___________.
Same
Groups
Inconsistencies
Non-matching rows

30. Explain the differences in how an ANSI Full Outer Join and a Full Outer Join using the UNION Operator work
X
MINUS
DICTIONARY
Structured Query Language

31. All SQL statements contained within a script must end with a _______________ - even if they are done in SQL Developer.
Details
COUNT(registration_date) - AVG (capacity) - MIN (capacity) - MAX (capacity)
Semicolon or forward slash
SELECT SYSDATE+1/96 - FROM dual

32. Which one of the following string functions tells you how many characters are in a string?
LENGTH
Recursive
Non-matching rows
LIKE

33. A _________ subquery returns a single column with a single row
Orphan
Scalar
999999.9999
DECODE

34. To place a line comment in your SQL statements - you first place a // at the beginning of the line.
FALSE
Leading-edge
Surrogate
MINUS

35. List 4 aggregate functions
VALUES
Any
COUNT(registration_date) - AVG (capacity) - MIN (capacity) - MAX (capacity)
Correlated

36. Subqueries can return...
Multiple rows
KEEP INDEX
Asterisk
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

37. PAGESIZE
Default is 14; when you use the default - you repeat the heading every 14 rows.
99.99
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.
Lists all objects accessible for the chosen database connection. Also lists a helpful dependencies report for accessing change impact.

38. Another name for a data dictionary view is __________________ or _________________.
Non-matching rows
Static or dynamic
Command returns the number of records returned by a query.
FALSE

39. The focus of the logical data model is _____________
Business problems
ROLLBACK
Static or dynamic
BETWEEN

40. Explicit data type conversion is preferable to Oracle's...
Implicit conversion
Groups
Business problems
Same

41. What is the syntax used to indicate that you are using the Oracle Outer Join operator?
+
COUNT(registration_date) - AVG (capacity) - MIN (capacity) - MAX (capacity)
Dynamic SQL is used to be continuously updated by the background processes in the Oracle instance but never by the user.
Lists all objects accessible for the chosen database connection. Also lists a helpful dependencies report for accessing change impact.

42. If a graphical representation of a table's box has __________ it means that the relationship is identifying.
A correct statement
X
FALSE
Rounded edges

43. FEEDBACK
F12
Command returns the number of records returned by a query.
COMMIT
RENAME - COPY - DROP - TRUNCATE - LOCK - & COMMENT

44. Explain how Oracle treats locks when a database is being updated and needs to be viewed by other users.
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
B-Tree Index
ON
COUNT(registration_date) - AVG (capacity) - MIN (capacity) - MAX (capacity)

45. LINESIZE
+
Command determines the total number of characters SQL *Plus displays in on line before beginning a new line.
Inconsistencies
TO_CHAR function

46. What does SQL stand for?
MODIFY
DECODE
Business problems
Structured Query Language

47. What does the following function return? SELECT LENGTH(NULL) - FROM dual
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
Null
GROUP BY
COUNT(registration_date) - AVG (capacity) - MIN (capacity) - MAX (capacity)

48. What do views do that makes them so useful for security?
User-defined reports
Hide data
Export Data
Default is 14; when you use the default - you repeat the heading every 14 rows.

49. Dynamic views begin with a ___________.
USER_ - ALL_ - DBA_ - and V$
Combine
V$
99.99

50. List the reasons that a subquery could not be unnested.
UTC
Null
STORAGE
X