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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 NEXTVAL and CURRVAL pseudocolumns can be used in which of the following SQL constructs? Select all that apply.
VALUES clause of an INSERT statement
Twice
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.
Null

2. What does the following function return? SELECT LENGTH(NULL) - FROM dual
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.
Null
+
4

3. Explain the steps needed to run a script in SQL Developer
Multiple rows
DESC dict;
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.
COUNT(registration_date) - AVG (capacity) - MIN (capacity) - MAX (capacity)

4. Self-joins are useful for performing comparisons and checking for ___________ in 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.
Three
Inconsistencies
Script

5. Explain how the SPOOL command is used and what program it can be used in.
Structured Query Language
Optional
SET clause of an UPDATE statement
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

6. Explain how Oracle treats locks when a database is being updated and needs to be viewed by other users.
Scale
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
Implicit conversion
B-Tree Index

7. List the steps performed by a correlated subquery.
**** 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
Asterisk
UNION operator
INTERSECT

8. When using the data NUMBER(10 -4) there will be _______ digits following the decimal point.
Command returns the number of records returned by a query.
Precision
4
12:00:00 A.M

9. Queries that are found in parentheses are done first - just as in the order of operations when doing...
2000
Mathematical equations
ANY
Location of the file

10. What are the main components of a ROWID?
When the table is small (unless your business rules require you too)
INNER JOIN
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.
Business problems

11. The data type definitions NUMBER(10) and NUMBER(10 -0) are the...
Same
VALUES
Mathematical equations
UTC

12. SELECT LIST of a subquery in an INSERT statement
SET clause of an UPDATE statement
The indexed column is part of an expression. In this case - consider creating a function-based index instead
Common column value
X

13. What is the main difference between the NOT EXISTS and the NOT IN operators?
Month ddth - yyyy
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.
The way NULL values are treated
Common column value

14. __________________ inserts the current date and time.
GROUP BY
Primary key/foreign key
FALSE
SYSDATE

15. To place a line comment in your SQL statements - you first place a // at the beginning of the line.
Self-joins
FALSE
Combine
Black

16. Converting a text literal to DATE format requires the use of the...
Command returns the number of records returned by a query.
The indexed column is part of an expression. In this case - consider creating a function-based index instead
FALSE
TO_CHAR function

17. A _____ is a query definition stored in the database that looks just like a table - but does not have any physical rows
X
RIGHT LEFT JOIN
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.
Null

18. The _______ operator determines common rows.
Groups
Asterisk
INTERSECT
F12

19. The ____________ keywords and the USING clause of the ANSI join syntax are mutually exclusive.
NATURAL JOIN
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 SCRIPT
Both MIN and MAX

20. To revert back to a state that happened before you ran your change statement - you issue a ____________ command.
Month ddth - yyyy
Non-matching rows
ROLLBACK
Running a script file

21. Write an SQL statement for SQL *Plus in which you want any unique menu items to be displayed from the restaurant table
12:00:00 A.M
Nested
SELECT DISTINCT menu FROM restaurant
Testing functions

22. What is the name of the key automatically generated from a sequence?
Surrogate key
Null
DD-MON-YY
Non-matching rows

23. Explain why constraints are used when building tables.

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24. What does SQL stand for?
Structured Query Language
4
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
ON

25. 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.
All
SELECT SYSDATE+1/96 - FROM dual
RIGHT LEFT JOIN
Export Data

26. FEEDBACK
DECODE
SELECT SYSDATE+1/96 - FROM dual
12:00:00 A.M
Command returns the number of records returned by a query.

27. The ________ operator cannot compare against a list of values.
SET clause of an UPDATE statement
Lists all objects accessible for the chosen database connection. Also lists a helpful dependencies report for accessing change impact.
Export Data
LIKE

28. It is considered good form to put all SQL commands in...
Combine
X
All caps
Columns

29. The RTRIM function is useful for eliminating ________ in a string.
Extra spaces
FALSE
COUNT(registration_date) - AVG (capacity) - MIN (capacity) - MAX (capacity)
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.

30. The using clause of the ANSI join syntax always assumes an...
Asterisk
Equijoin and identical column names
Columns
STORAGE

31. When you have issued a DELETE command - you can still ________ those rows and restore the information.
Retrieve
Scale
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.
ROLLBACK

32. Comparison operators can compare multiple _________________.
ANY
MINUS
Columns
Twice

33. The ___________ operator tests whether a matching row cannot be found.
Structured Query Language
Time zone
Precision
X

34. The term ____________ ___________ is used to express a join that satisfies the join condition.
B-Tree Index
INNER JOIN
A correct statement
@ or START

35. A _________ subquery returns a single column with a single row
Scalar
@ or START
DROP INDEX need_to_pass_i
Inconsistencies

36. The DUAL table can be used for...
Testing functions
Control - Revoke - Define - TRUNCATE Manipulate - MERGE
VALUES clause of an INSERT statement
SELECT SYSDATE+1/96 - FROM dual

37. Which operator is most commonly used?
UNION
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
Inconsistencies
X

38. Returns rows if the condition is true for all the values in the list
All
Multiple rows
Rounded edges
CLOB

39. When column names on the tables are different - you use the ______ condition.
MODIFY
SYSDATE
Crow's foot
ON

40. SELECT * FROM instructor ORDER BY phone
A correct statement
MODIFY
BETWEEN
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.

41. Information that is returned after you run your statement are found in the __________ tab in SQL Developer.
Results
USER_ - ALL_ - DBA_ - and V$
Twice
999999.9999

42. The ALTER SESSION statement can change the session's...
Time zone
Logical unit of work
Hide data
BETWEEN

43. What is the Oracle data dictionary called that contains a set of tables and views containing the data about the database?
DICTIONARY
ALL_OBJECTS
Any
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.

44. What do views do that makes them so useful for security?
Precision
Logical unit of work
Has not changed the name
Hide data

45. To restart a sequence at a lower number - you can drop and ________ the sequence.
Both MIN and MAX
DECODE
Columns
Re-create

46. ____________ are useful for analyzing and exploring the relationships within your data
The way NULL values are treated
SUM
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.
Self-joins

47. Checks whether any value in the list makes the condition true.
Testing functions
Any
Black
Script

48. When disabling a unique or primary key - you can keep the index if you specify the __________________ clause in the ALTER TABLE statement.
KEEP INDEX
Actual column
SYSDATE
Structured Query Language

49. _________ and __________ functions are opposites of each other and provide a value in a group of rows.
Precision
Self-joins
Both MIN and MAX
BETWEEN

50. 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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