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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. The same function can be used ______ in a SELECT statement.
V$
Twice
Null
Logical unit of work

2. A calculation with a null always yields...
Results
Another null
Correlated
Structured Query Language

3. The ____________ keywords and the USING clause of the ANSI join syntax are mutually exclusive.
Asterisk
BETWEEN
Common column value
NATURAL JOIN

4. A transaction is a...
Mathematical equations
Logical unit of work
ADD_MONTHS function
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

5. Write a solution that adds 20 minutes to a given date.
Results
Semicolon or forward slash
SELECT SYSDATE+1/96 - FROM dual
Combine

6. Explain what a static data dictionary view is and how it is used
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
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.
Structured Query Language
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.

7. What is the syntax used to indicate that you are using the Oracle Outer Join operator?
+
The way NULL values are treated
RIGHT LEFT JOIN
Equijoin and correlated subquery

8. Explain the differences in how an ANSI Full Outer Join and a Full Outer Join using the UNION Operator work
4000
Any
ALL_OBJECTS
X

9. What do views do that makes them so useful for security?
Self-joins
Hide data
DD-MON-YY
2000

10. The purpose of the HAVING clause is to eliminate___________.
Groups
Both MIN and MAX
Results
Scalar

11. Users can only see changes made to a database once they have been...
Same
DD-MON-YY
Committed
Three

12. Write an SQL statement for SQL *Plus in which you want any unique menu items to be displayed from the restaurant table
Month ddth - yyyy
Results
SELECT DISTINCT menu FROM restaurant
LIKE

13. The ______ operator compares a list of values for equivalency
ANY
Command returns the number of records returned by a query.
4000
KEEP INDEX

14. 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.
Testing functions
VALUES
VALUES clause of an INSERT statement
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

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

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16. When is it not a good idea to use an index?
Inconsistencies
Export Data
When the table is small (unless your business rules require you too)
BETWEEN

17. Comparison operators can compare multiple _________________.
X
Columns
Twice
Testing functions

18. 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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19. Write a statement for SQL*Plus that shows the dictionary.
Self-joins
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.
DESC dict;
X

20. The COUNT function uses the __________ wildcard.
Asterisk
MODIFY
Equijoin and identical column names
Optional

21. 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.
Crow's foot
RIGHT LEFT JOIN
All caps
UTC

22. The data type definitions NUMBER(10) and NUMBER(10 -0) are the...
Default is 14; when you use the default - you repeat the heading every 14 rows.
Dynamic SQL is used to be continuously updated by the background processes in the Oracle instance but never by the user.
Same
VALUES

23. List the steps performed by a correlated subquery.
MINUS
Null
Implicit conversion
**** 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

24. The query retrieves more than 5 to 15 percent of the rows
Dynamic SQL is used to be continuously updated by the background processes in the Oracle instance but never by the user.
The indexed column is part of an expression. In this case - consider creating a function-based index instead
ON
Time zone

25. List 4 aggregate functions
COUNT(registration_date) - AVG (capacity) - MIN (capacity) - MAX (capacity)
Any
Lists all objects accessible for the chosen database connection. Also lists a helpful dependencies report for accessing change impact.
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

26. The key that most database designers prefer and is chosen by the system is the _____________ key.
X
Both MIN and MAX
Surrogate
X

27. It is considered good form to put all SQL commands in...
User-defined reports
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
X
All caps

28. Match each of the SQL commands on the left with a verb from the list.
SYSDATE
Export Data
Control - Revoke - Define - TRUNCATE Manipulate - MERGE
Twice

29. What is the tab in SQL Developer where data dictionary view information can be found?
SELECT SYSDATE+1/96 - FROM dual
Details
2000
Equijoin and correlated subquery

30. The ___________ operator tests whether a matching row cannot be found.
X
When the table is small (unless your business rules require you too)
Actual column
SET clause of an UPDATE statement

31. You use the _________ keyword to add columns or constraints to a table.
4000
DICT_COLUMNS
ADD
When the table is small (unless your business rules require you too)

32. A join across three tables can be expressed with the ________ join syntax.
ANSI
Re-create
Actual column
Default is 14; when you use the default - you repeat the heading every 14 rows.

33. 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.
FALSE
12:00:00 A.M
Another null
Structured Query Language

34. 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.
X
Surrogate
COUNT(registration_date) - AVG (capacity) - MIN (capacity) - MAX (capacity)

35. In a view you can give a column a different name than it has in the...
Command returns the number of records returned by a query.
Three
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
Parent table

36. To place a line comment in your SQL statements - you first place a // at the beginning of the line.
STORAGE
FALSE
Three
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. Write a statement that drops the index need_to_pass_i
SET clause of an UPDATE statement
DROP INDEX need_to_pass_i
TO_CHAR function
Self-joins

38. Explain how you can optimize your queries with subqueries and the main advantage of doing so.
Combine
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
Null
Logical unit of work

39. SQL Developer's ____________________ option allows you to selectively export certain rows and columns.
Logical unit of work
Export Data
RENAME just_two_more_weeks TO finally_i
Retrieve

40. What is the keyboard shortcut for the ROLLBACK command?
Crow's foot
A correct statement
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

41. The TRUNC function on a date without a format model truncates the timestamp to...
12:00:00 A.M
Parent table
Default is 14; when you use the default - you repeat the heading every 14 rows.
Month ddth - yyyy

42. _________ and __________ functions are opposites of each other and provide a value in a group of rows.
Both MIN and MAX
Scale
Control - Revoke - Define - TRUNCATE Manipulate - MERGE
Inconsistencies

43. Dynamic views begin with a ___________.
SET clause of an UPDATE statement
Equijoin
V$
Same

44. An outer join includes the result rows returned by an __________ plus extra rows where no matches are found.
Time zone
Groups
Equijoin
Command returns the number of records returned by a query.

45. In SQL Developer field names and table names are shown in the color _______.
Black
Scalar
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.
Semicolon or forward slash

46. PAGESIZE
Default is 14; when you use the default - you repeat the heading every 14 rows.
Surrogate key
Leading-edge
Dynamic SQL is used to be continuously updated by the background processes in the Oracle instance but never by the user.

47. How many characters can you have using the VARCHAR data type?
Running a script file
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
4000
Parent table

48. You can __________ DISTINCT and a GROUP BY clause in the same SELECT statement.
Command determines the total number of characters SQL *Plus displays in on line before beginning a new line.
Running a script file
X
Combine

49. __________________ inserts the current date and time.
SYSDATE
Optional
F12
Retrieve

50. The focus of the logical data model is _____________
Business problems
Orphan
Testing functions
Equijoin