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. You use the __________ keyword to change characteristics of a column.
Common column value
RUN SCRIPT
MODIFY
LIKE

2. Write a statement for SQL*Plus that shows the dictionary.
ANSI
Control - Revoke - Define - TRUNCATE Manipulate - MERGE
Command returns the number of records returned by a query.
DESC dict;

3. If a graphical representation of a table's box has __________ it means that the relationship is identifying.
Groups
Rounded edges
Null
Location of the file

4. Explain how Dynamic SQL is used and give an example of a Dynamic SQL statement.
VALUES
Dynamic SQL is used to be continuously updated by the background processes in the Oracle instance but never by the user.
Control - Revoke - Define - TRUNCATE Manipulate - MERGE
Common column value

5. When you create a report in SQL Developer all the column names must match identically the names of the columns found in the tables you are referencing.
ANY
FALSE
Scalar
12:00:00 A.M

6. Information that is returned after you run your statement are found in the __________ tab in SQL Developer.
12:00:00 A.M
Results
Common column value
UNION

7. Explain what a static data dictionary view is and how it is used
Nested
UNION
COUNT(registration_date) - AVG (capacity) - MIN (capacity) - MAX (capacity)
The static data dictionary stores details about database objects - such as tables - indexes - and views. Whenever a new object is added or an object is changed - data about the object is recorded in the data dictionary.

8. SELECT * FROM instructor ORDER BY phone
+
Scalar
Lists all objects accessible for the chosen database connection. Also lists a helpful dependencies report for accessing change impact.
A correct statement

9. What is the most common DATE format found in SQL?
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
NATURAL JOIN
12:00:00 A.M
DD-MON-YY

10. When using the following data: NUMBER(10 -4) - the # 10 is called the __________.
NATURAL JOIN
Precision
Any
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

11. What is the tab in SQL Developer where data dictionary view information can be found?
RUN SCRIPT
Static or dynamic
Details
X

12. Match each of the SQL commands on the left with a verb from the list.
Combine
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
Control - Revoke - Define - TRUNCATE Manipulate - MERGE
999999.9999

13. The ______ operator compares a list of values for equivalency
SELECT SYSDATE+1/96 - FROM dual
MODIFY
ANY
Control - Revoke - Define - TRUNCATE Manipulate - MERGE

14. When using the following data: NUMBER(10 -4) - the # 4 is called the __________.
Scalar
Scale
99.99
NATURAL JOIN

15. 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
Logical unit of work
Default is 14; when you use the default - you repeat the heading every 14 rows.
RIGHT LEFT JOIN

16. Explicit data type conversion is preferable to Oracle's...
ALL_OBJECTS
FALSE
Static or dynamic
Implicit conversion

17. Write an SQL statement for SQL *Plus in which you want any unique menu items to be displayed from the restaurant table
F12
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
Command determines the total number of characters SQL *Plus displays in on line before beginning a new line.
SELECT DISTINCT menu FROM restaurant

18. 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?
Export Data
DICTIONARY
COMMIT
X

19. A _____ is a query definition stored in the database that looks just like a table - but does not have any physical rows
X
Actual column
F12
ON

20. Explain what is found in the All Objects report folder in SQL Developer
Running a script file
Primary key/foreign key
Lists all objects accessible for the chosen database connection. Also lists a helpful dependencies report for accessing change impact.
Scale

21. The time zone displacement value indicates the time difference from _______.
RENAME just_two_more_weeks TO finally_i
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
UTC
Command returns the number of records returned by a query.

22. Instead of using the Oracle Outer Join Operator or the ANSI syntax - you can achieve the same result with two SQL statements: ____________ and a ____________
Time zone
COMMIT
Equijoin and correlated subquery
The way NULL values are treated

23. You can simplify the writing of SQL statements by writing SQL _________ that generate and execute other SQL statements.
Semicolon or forward slash
COMMIT
Rounded edges
Script

24. What is the data type you can use if you need an unlimited number of textual characters?
BETWEEN
999999.9999
CLOB
Committed

25. The Nonequijoin can use the ________________ operator to construct joins that are not based on equality of values.
ON
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
BETWEEN
999999.9999

26. How many characters can be stored in the CHAR column/field?
Location of the file
2000
DROP INDEX need_to_pass_i
INNER JOIN

27. A _________ subquery returns a single column with a single row
VALUES clause of an INSERT statement
Optional
Scalar
RENAME just_two_more_weeks TO finally_i

28. The ALTER SESSION statement can change the session's...
BETWEEN
LIKE
Leading-edge
Time zone

29. The using clause of the ANSI join syntax always assumes an...
Groups
Equijoin and identical column names
IN ANY ALL SOME
ON

30. When you want to run a script in either SQL*Plus or SQL Developer - you can use a ______ or the _________ command.
Time zone
Structured Query Language
Script
@ or START

31. The RTRIM function is useful for eliminating ________ in a string.
Testing functions
ROLLBACK
ADD
Extra spaces

32. Returns rows if the condition is true for all the values in the list
All
Surrogate key
RENAME - COPY - DROP - TRUNCATE - LOCK - & COMMENT
Same

33. Queries that are found in parentheses are done first - just as in the order of operations when doing...
LIKE
Same
USER_ - ALL_ - DBA_ - and V$
Mathematical equations

34. The key that most database designers prefer and is chosen by the system is the _____________ key.
INNER JOIN
Any
MINUS
Surrogate

35. When is it not a good idea to use an index?
4000
When the table is small (unless your business rules require you too)
IN ANY ALL SOME
User-defined reports

36. Joins involving multiple columns must always follow the ____________ relationship path.
Export Data
Same
Committed
Primary key/foreign key

37. Subqueries can return...
Common column value
Multiple rows
VALUES clause of an INSERT statement
FALSE

38. To revert back to a state that happened before you ran your change statement - you issue a ____________ command.
Semicolon or forward slash
ANSI
+
ROLLBACK

39. When writing an ANSI outer join - the keywords _________ OUTER and _________ OUTER are added to the __________ keyword to indicate the rows from which table to use.
RIGHT LEFT JOIN
Both MIN and MAX
SUM
Running a script file

40. Explain how Oracle treats locks when a database is being updated and needs to be viewed by other users.
IN ANY ALL SOME
Logical unit of work
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
All caps

41. When you have issued a DELETE command - you can still ________ those rows and restore the information.
Testing functions
Another null
Retrieve
COMMIT

42. You can __________ DISTINCT and a GROUP BY clause in the same SELECT statement.
ADD
Scale
RUN SCRIPT
Combine

43. When using the following data: NUMBER(10 -4) - the lowest number you can possibly have is __________.
Mathematical equations
999999.9999
TO_CHAR function
4

44. In SQL Developer field names and table names are shown in the color _______.
F12
Black
999999.9999
User-defined reports

45. Write the syntax to rename index just_two_more_weeks_i to finally_i
UNION
RENAME just_two_more_weeks TO finally_i
RUN SCRIPT
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.

46. Comparison operators can compare multiple _________________.
X
Columns
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.
Logical unit of work

47. What is the main difference between the NOT EXISTS and the NOT IN operators?
User-defined reports
Has not changed the name
Same
The way NULL values are treated

48. What is Oracle's most popular index storage structure?
Primary key/foreign key
B-Tree Index
SELECT SYSDATE+1/96 - FROM dual
ADD

49. The DUAL table can be used for...
Implicit conversion
Running a script file
Testing functions
DICT_COLUMNS

50. An outer join includes the result rows returned by an __________ plus extra rows where no matches are found.
Leading-edge
Equijoin
VALUES
Another null