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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. It is considered good form to put all SQL commands in...
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
Testing functions
All caps
Retrieve

2. The COUNT function uses the __________ wildcard.
Structured Query Language
Asterisk
ANY
Correlated

3. When using the following data: NUMBER(10 -4) - the # 10 is called the __________.
Same
MODIFY
LIKE
Precision

4. Queries that are found in parentheses are done first - just as in the order of operations when doing...
Mathematical equations
Orphan
VALUES
Non-matching rows

5. To revert back to a state that happened before you ran your change statement - you issue a ____________ command.
Run scripts
Multiple rows
ROLLBACK
DROP INDEX need_to_pass_i

6. Which format mask displays December 31st - 1999?
Any
STORAGE
VALUES clause of an INSERT statement
Month ddth - yyyy

7. The term ____________ ___________ is used to express a join that satisfies the join condition.
FALSE
Control - Revoke - Define - TRUNCATE Manipulate - MERGE
Running a script file
INNER JOIN

8. When using the following data: NUMBER(10 -4) - the lowest number you can possibly have is __________.
999999.9999
Both MIN and MAX
DROP INDEX need_to_pass_i
DICTIONARY

9. What is the maximum value for a column defined as NUMBER(4 -2)?
99.99
Self-joins
Re-create
Leading-edge

10. When using the data NUMBER(10 -4) there will be _______ digits following the decimal point.
VALUES clause of an INSERT statement
4
Implicit conversion
Fractional seconds

11. The TRUNC function on a date without a format model truncates the timestamp to...
99.99
GROUP BY
12:00:00 A.M
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

12. What do views do that makes them so useful for security?
Same
Hide data
Structured Query Language
Extra spaces

13. Converting a text literal to DATE format requires the use of the...
LIKE
Any
TO_CHAR function
NATURAL JOIN

14. NUMBER functions can be...
Nested
INTERSECT
X
Equijoin and identical column names

15. When returning multiple rows - a subquery must contain the _____ - _____ - _____ - or ______ operator - otherwise Oracle will return an error
Location of the file
IN ANY ALL SOME
Re-create
FALSE

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

17. Explicit data type conversion is preferable to Oracle's...
MODIFY
Running a script file
Implicit conversion
SYSDATE

18. Explain what is found in the All Objects report folder in SQL Developer
Lists all objects accessible for the chosen database connection. Also lists a helpful dependencies report for accessing change impact.
Fractional seconds
Groups
Three

19. Explain how you can optimize your queries with subqueries and the main advantage of doing so.
Lists all objects accessible for the chosen database connection. Also lists a helpful dependencies report for accessing change impact.
Asterisk
Groups
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

20. The purpose of the HAVING clause is to eliminate___________.
Groups
Structured Query Language
Implicit conversion
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.

21. Self-joins are useful for performing comparisons and checking for ___________ in data.
Re-create
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
Inconsistencies
Combine

22. What is Oracle's most popular index storage structure?
F12
UNION operator
B-Tree Index
The indexed column is part of an expression. In this case - consider creating a function-based index instead

23. The ____________ keywords and the USING clause of the ANSI join syntax are mutually exclusive.
LIKE
MINUS
NATURAL JOIN
Month ddth - yyyy

24. What is the most common DATE format found in SQL?
DD-MON-YY
Control - Revoke - Define - TRUNCATE Manipulate - MERGE
IN ANY ALL SOME
4000

25. SELECT * FROM instructor ORDER BY phone
A correct statement
MODIFY
FALSE
DICTIONARY

26. When disabling a unique or primary key - you can keep the index if you specify the __________________ clause in the ALTER TABLE statement.
99.99
KEEP INDEX
B-Tree Index
SELECT DISTINCT menu FROM restaurant

27. In a view you can give a column a different name than it has in the...
Parent table
Location of the file
Running a script file
BETWEEN

28. A join across three tables can be expressed with the ________ join syntax.
Twice
ANSI
INTERSECT
Static or dynamic

29. Explain how Substitution Variables are used when writing scripts.
Data
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.
Run scripts
Time zone

30. The using clause of the ANSI join syntax always assumes an...
Multiple rows
Null
Equijoin and identical column names
Orphan

31. _________ and __________ functions are opposites of each other and provide a value in a group of rows.
Both MIN and MAX
Time zone
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.
Scale

32. When you run a script in SQL*Plus you must give the...
FALSE
Location of the file
Columns
Recursive

33. What is the first column of a composite index called?
RENAME - COPY - DROP - TRUNCATE - LOCK - & COMMENT
ROLLBACK
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.
Leading-edge

34. The ____________ clause on a CREATE TABLE statement can specify how much space to allocate.
STORAGE
Running a script file
Lists all objects accessible for the chosen database connection. Also lists a helpful dependencies report for accessing change impact.
A correct statement

35. Write an SQL statement for SQL *Plus in which you want any unique menu items to be displayed from the restaurant table
VALUES clause of an INSERT statement
LENGTH
SELECT DISTINCT menu FROM restaurant
Multiple rows

36. The query retrieves more than 5 to 15 percent of the rows
Logical unit of work
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
The indexed column is part of an expression. In this case - consider creating a function-based index instead
Groups

37. You use the _________ keyword to add columns or constraints to a table.
Location of the file
Surrogate key
ADD
X

38. A transaction is a...
Logical unit of work
Three
Scalar
VALUES

39. An outer join includes the result rows returned by an __________ plus extra rows where no matches are found.
Optional
Equijoin
ADD_MONTHS function
UNION

40. The _______ function lets you perform if-then-else functionality with the SQL language.
Data
Testing functions
DECODE
ANY

41. Which operator is most commonly used?
SET clause of an UPDATE statement
SELECT SYSDATE+1/96 - FROM dual
UNION
IN ANY ALL SOME

42. FEEDBACK
GROUP BY
ALL_OBJECTS
Three
Command returns the number of records returned by a query.

43. 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.
Asterisk
VALUES
RENAME just_two_more_weeks TO finally_i
The way NULL values are treated

44. What does SQL stand for?
Structured Query Language
Hide data
Both MIN and MAX
KEEP INDEX

45. _________ rows are not allowed in the relational model.
COUNT(registration_date) - AVG (capacity) - MIN (capacity) - MAX (capacity)
Has not changed the name
Orphan
Run scripts

46. A calculation with a null always yields...
Fractional seconds
Another null
DICT_COLUMNS
KEEP INDEX

47. Which one of the following string functions tells you how many characters are in a string?
F12
Twice
LENGTH
Null

48. Users can only see changes made to a database once they have been...
Committed
LENGTH
Implicit conversion
Columns

49. You can simplify the writing of SQL statements by writing SQL _________ that generate and execute other SQL statements.
Correlated
Script
ADD
FALSE

50. Explain how the SPOOL command is used and what program it can be used in.
Null
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
Scalar
All caps