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 name of the view where you can find the collection of static and data dictionary tables and views - along with their descriptions?
DICTIONARY
Data
INTERSECT
2000

2. The TRUNC function on a date without a format model truncates the timestamp to...
Columns
X
Rounded edges
12:00:00 A.M

3. The purpose of the HAVING clause is to eliminate___________.
ALL_OBJECTS
Groups
Null
RIGHT LEFT JOIN

4. When using the following data: NUMBER(10 -4) - the lowest number you can possibly have is __________.
Lists all objects accessible for the chosen database connection. Also lists a helpful dependencies report for accessing change impact.
Equijoin and identical column names
Another null
999999.9999

5. Explain how Dynamic SQL is used and give an example of a Dynamic SQL statement.
Month ddth - yyyy
Has not changed the name
Dynamic SQL is used to be continuously updated by the background processes in the Oracle instance but never by the user.
Same

6. The TIMESTAMP WITH LOCAL TIME ZONE data type allows...
12:00:00 A.M
Logical unit of work
User-defined reports
Fractional seconds

7. Instead of using the Oracle Outer Join Operator or the ANSI syntax - you can achieve the same result with two SQL statements: ____________ and a ____________
Orphan
TO_CHAR function
Equijoin and correlated subquery
Non-matching rows

8. Explain what a static data dictionary view is and how it is used
Testing functions
Precision
Primary key/foreign key
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.

9. When you have issued a DELETE command - you can still ________ those rows and restore the information.
Primary key/foreign key
Retrieve
**** 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
Logical unit of work

10. The ______ operator compares a list of values for equivalency
X
ANY
Dynamic SQL is used to be continuously updated by the background processes in the Oracle instance but never by the user.
UNION

11. Write the syntax to rename index just_two_more_weeks_i to finally_i
2000
RENAME just_two_more_weeks TO finally_i
Month ddth - yyyy
Surrogate

12. Write an SQL statement for SQL *Plus in which you want any unique menu items to be displayed from the restaurant table
INTERSECT
SELECT DISTINCT menu FROM restaurant
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
RUN SCRIPT

13. _________ rows are not allowed in the relational model.
4000
UNION operator
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.
Orphan

14. Queries that are found in parentheses are done first - just as in the order of operations when doing...
Mathematical equations
@ or START
Command returns the number of records returned by a query.
ALL_OBJECTS

15. If a graphical representation of a table's box has __________ it means that the relationship is identifying.
Leading-edge
Rounded edges
DROP INDEX need_to_pass_i
COMMIT

16. _________________ relationships are always optional relationships.
Recursive
Lists all objects accessible for the chosen database connection. Also lists a helpful dependencies report for accessing change impact.
Scale
Fractional seconds

17. The same function can be used ______ in a SELECT statement.
Twice
+
Primary key/foreign key
Null

18. How many characters can you have using the VARCHAR data type?
All caps
4000
UNION
X

19. In a view you can give a column a different name than it has in the...
Time zone
Parent table
SYSDATE
Dynamic SQL is used to be continuously updated by the background processes in the Oracle instance but never by the user.

20. Another name for a data dictionary view is __________________ or _________________.
Non-matching rows
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
Static or dynamic
MINUS

21. List the different types of data dictionary views.
Rounded edges
Retrieve
USER_ - ALL_ - DBA_ - and V$
999999.9999

22. Explicit data type conversion is preferable to Oracle's...
BETWEEN
Implicit conversion
Self-joins
Details

23. Dynamic views begin with a ___________.
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
RENAME - COPY - DROP - TRUNCATE - LOCK - & COMMENT
V$
Multiple rows

24. You can __________ DISTINCT and a GROUP BY clause in the same SELECT statement.
Mathematical equations
4000
Combine
Equijoin

25. Oracle uses the outer join operator to indicate that nulls are shown for...
Non-matching rows
Semicolon or forward slash
Data
Command returns the number of records returned by a query.

26. When is it not a good idea to use an index?
Combine
Three
When the table is small (unless your business rules require you too)
RIGHT LEFT JOIN

27. When returning multiple rows - a subquery must contain the _____ - _____ - _____ - or ______ operator - otherwise Oracle will return an error
INNER JOIN
Surrogate key
Primary key/foreign key
IN ANY ALL SOME

28. The term ____________ ___________ is used to express a join that satisfies the join condition.
Black
Control - Revoke - Define - TRUNCATE Manipulate - MERGE
Run scripts
INNER JOIN

29. Checks whether any value in the list makes the condition true.
Any
Leading-edge
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.
MODIFY

30. The _______ function adds values together for a group of rows.
Multiple rows
SUM
+
The way NULL values are treated

31. Which operator is most commonly used?
Recursive
UNION
BETWEEN
2000

32. The _____________ clause determines how rows are grouped.
RUN SCRIPT
Scale
GROUP BY
Lists all objects accessible for the chosen database connection. Also lists a helpful dependencies report for accessing change impact.

33. To place a line comment in your SQL statements - you first place a // at the beginning of the line.
Three
Business problems
FALSE
DICT_COLUMNS

34. The COUNT function is useful for determining whether a table has...
99.99
Actual column
Data
Groups

35. What is the name of the key automatically generated from a sequence?
Run scripts
Surrogate key
Command returns the number of records returned by a query.
X

36. When disabling a unique or primary key - you can keep the index if you specify the __________________ clause in the ALTER TABLE statement.
KEEP INDEX
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.
SELECT DISTINCT menu FROM restaurant
Orphan

37. List the steps performed by a correlated subquery.
INTERSECT
**** 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
Static or dynamic
FALSE

38. Which one of the following string functions tells you how many characters are in a string?
Retrieve
ANSI
LENGTH
Run scripts

39. What is the Oracle data dictionary called that contains a set of tables and views containing the data about the database?
ALL_OBJECTS
Semicolon or forward slash
X
TO_CHAR function

40. The ROWID pseudocolumn is not an ________- but it acts like one.
Actual column
STORAGE
SELECT SYSDATE+1/96 - 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

41. Match each of the SQL commands on the left with a verb from the list.
Control - Revoke - Define - TRUNCATE Manipulate - MERGE
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
Precision
Default is 14; when you use the default - you repeat the heading every 14 rows.

42. Write a solution that adds 20 minutes to a given date.
SELECT SYSDATE+1/96 - FROM dual
MINUS
FALSE
Logical unit of work

43. What is the command you would type into SQL*Plus if you needed to know the definition for each column of a table?
Static or dynamic
Leading-edge
RIGHT LEFT JOIN
DICT_COLUMNS

44. Explain the steps needed to run a script in SQL Developer
DD-MON-YY
ANY
Null
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.

45. The ___________ operator tests whether a matching row cannot be found.
All caps
BETWEEN
DICTIONARY
X

46. Explain in detail the impact of INDEXES and how they are used by Oracle.
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
RIGHT LEFT JOIN
ANSI
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.

47. SELECT LIST of a subquery in an INSERT statement
NATURAL JOIN
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
SET clause of an UPDATE statement
User-defined reports

48. ____________ are useful for analyzing and exploring the relationships within your data
Self-joins
When the table is small (unless your business rules require you too)
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.
Static or dynamic

49. What is the syntax used to indicate that you are using the Oracle Outer Join operator?
Semicolon or forward slash
Combine
+
Command determines the total number of characters SQL *Plus displays in on line before beginning a new line.

50. You can use the ________________ to subtract months from a given date.
B-Tree Index
BETWEEN
ADD_MONTHS function
All