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. Information that is returned after you run your statement are found in the __________ tab in SQL Developer.
X
Correlated
INTERSECT
Results

2. A calculation with a null always yields...
ON
Surrogate
The way NULL values are treated
Another null

3. When you run a script in SQL*Plus you must give the...
MODIFY
X
Details
Location of the file

4. Match each of the SQL commands on the left with a verb from the list.
999999.9999
X
Command determines the total number of characters SQL *Plus displays in on line before beginning a new line.
Control - Revoke - Define - TRUNCATE Manipulate - MERGE

5. What is the Oracle data dictionary called that contains a set of tables and views containing the data about the database?
@ or START
VALUES clause of an INSERT statement
ALL_OBJECTS
Retrieve

6. _________________ relationships are always optional relationships.
Recursive
RENAME just_two_more_weeks TO finally_i
BETWEEN
Structured Query Language

7. To restart a sequence at a lower number - you can drop and ________ the sequence.
Equijoin
Re-create
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.
Combine

8. Write the syntax to rename index just_two_more_weeks_i to finally_i
RENAME just_two_more_weeks TO finally_i
Nested
Lists all objects accessible for the chosen database connection. Also lists a helpful dependencies report for accessing change impact.
MODIFY

9. A transaction is a...
Surrogate
Logical unit of work
Data
Month ddth - yyyy

10. Explain how the SPOOL command is used and what program it can be used in.
Twice
Committed
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
DICTIONARY

11. When using the following data: NUMBER(10 -4) - the # 4 is called the __________.
ALL_OBJECTS
ROLLBACK
Scale
SUM

12. _________ rows are not allowed in the relational model.
Semicolon or forward slash
Another null
Three
Orphan

13. Explain what a static data dictionary view is and how it is used
Orphan
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.
SUM
4

14. What is the keyboard shortcut for the ROLLBACK command?
RENAME - COPY - DROP - TRUNCATE - LOCK - & COMMENT
TO_CHAR 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
F12

15. Write a statement that drops the index need_to_pass_i
Parent table
X
**** 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
DROP INDEX need_to_pass_i

16. What is the main difference between the NOT EXISTS and the NOT IN operators?
Dynamic SQL is used to be continuously updated by the background processes in the Oracle instance but never by the user.
DD-MON-YY
The way NULL values are treated
X

17. The purpose of the HAVING clause is to eliminate___________.
VALUES clause of an INSERT statement
Groups
Default is 14; when you use the default - you repeat the heading every 14 rows.
ANY

18. How many characters can be stored in the CHAR column/field?
2000
INNER JOIN
Logical unit of work
Re-create

19. What do views do that makes them so useful for security?
Scalar
Hide data
@ or START
BETWEEN

20. The NEXTVAL and CURRVAL pseudocolumns can be used in which of the following SQL constructs? Select all that apply.
Any
BETWEEN
VALUES clause of an INSERT statement
Asterisk

21. Converting a text literal to DATE format requires the use of the...
Running a script file
TO_CHAR function
4
Run scripts

22. In a view you can give a column a different name than it has in the...
NATURAL JOIN
Nested
CLOB
Parent table

23. When using the following data: NUMBER(10 -4) - the lowest number you can possibly have is __________.
Inconsistencies
A correct statement
999999.9999
KEEP INDEX

24. The COUNT function is useful for determining whether a table has...
Dynamic SQL is used to be continuously updated by the background processes in the Oracle instance but never by the user.
SELECT DISTINCT menu FROM restaurant
RUN SCRIPT
Data

25. When you want to run a script in either SQL*Plus or SQL Developer - you can use a ______ or the _________ command.
Data
COUNT(registration_date) - AVG (capacity) - MIN (capacity) - MAX (capacity)
@ or START
Semicolon or forward slash

26. Which operator is most commonly used?
Extra spaces
Multiple rows
UNION
Both MIN and MAX

27. When returning multiple rows - a subquery must contain the _____ - _____ - _____ - or ______ operator - otherwise Oracle will return an error
SUM
Multiple rows
IN ANY ALL SOME
MINUS

28. List 4 aggregate functions
COUNT(registration_date) - AVG (capacity) - MIN (capacity) - MAX (capacity)
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.
When the table is small (unless your business rules require you too)
RENAME - COPY - DROP - TRUNCATE - LOCK - & COMMENT

29. You can use the ________________ to subtract months from a given date.
RENAME - COPY - DROP - TRUNCATE - LOCK - & COMMENT
ADD_MONTHS function
99.99
SYSDATE

30. The ALTER SESSION statement can change the session's...
B-Tree Index
Time zone
Run scripts
Leading-edge

31. What is the command you would type into SQL*Plus if you needed to know the definition for each column of a table?
V$
DICT_COLUMNS
Crow's foot
Parent table

32. The __________ operator is inclusive of the two values specified.
BETWEEN
Run scripts
Surrogate
Semicolon or forward slash

33. The COUNT function uses the __________ wildcard.
NATURAL JOIN
LIKE
Committed
Asterisk

34. Explain how Dynamic SQL is used and give an example of a Dynamic SQL statement.
Extra spaces
SUM
COUNT(registration_date) - AVG (capacity) - MIN (capacity) - MAX (capacity)
Dynamic SQL is used to be continuously updated by the background processes in the Oracle instance but never by the user.

35. What is the maximum value for a column defined as NUMBER(4 -2)?
+
2000
Data
99.99

36. What is Oracle's most popular index storage structure?
B-Tree Index
Extra spaces
Multiple rows
STORAGE

37. The using clause of the ANSI join syntax always assumes an...
Equijoin and identical column names
Precision
Self-joins
COMMIT

38. A _____ is a query definition stored in the database that looks just like a table - but does not have any physical rows
Lists all objects accessible for the chosen database connection. Also lists a helpful dependencies report for accessing change impact.
X
When the table is small (unless your business rules require you too)
BETWEEN

39. 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.
Extra spaces
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
UNION

40. Self-joins are useful for performing comparisons and checking for ___________ in data.
Testing functions
Black
DECODE
Inconsistencies

41. What is the name of the key automatically generated from a sequence?
4
Precision
Surrogate key
Fractional seconds

42. The _____________ clause determines how rows are grouped.
When the table is small (unless your business rules require you too)
All caps
Month ddth - yyyy
GROUP BY

43. When writing the syntax for finding information on three or more tables - the parenthesis around the ON clause is...
Script
SET clause of an UPDATE statement
Optional
Leading-edge

44. What is the data type you can use if you need an unlimited number of textual characters?
Results
CLOB
Re-create
BETWEEN

45. It is considered good form to put all SQL commands in...
All caps
The indexed column is part of an expression. In this case - consider creating a function-based index instead
Running a script file
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.

46. An outer join includes the result rows returned by an __________ plus extra rows where no matches are found.
Inconsistencies
Equijoin
Default is 14; when you use the default - you repeat the heading every 14 rows.
Multiple rows

47. Explain in detail the impact of INDEXES and how they are used by Oracle.
Run scripts
Asterisk
ROLLBACK
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

48. The data type definitions NUMBER(10) and NUMBER(10 -0) are the...
BETWEEN
Running a script file
Same
Actual column

49. Checks whether any value in the list makes the condition true.
Actual column
Multiple rows
Crow's foot
Any

50. Explain how Oracle treats locks when a database is being updated and needs to be viewed by other users.
Correlated
INTERSECT
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
Data