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. When using the following data: NUMBER(10 -4) - the # 10 is called the __________.
Precision
Recursive
Equijoin and correlated subquery
X

2. What is the name of the key automatically generated from a sequence?
RUN SCRIPT
Dynamic SQL is used to be continuously updated by the background processes in the Oracle instance but never by the user.
Surrogate key
Month ddth - yyyy

3. To equijoin a table with another table involves matching the...
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
Columns
Export Data
Common column value

4. To revert back to a state that happened before you ran your change statement - you issue a ____________ command.
ROLLBACK
Common column value
UNION operator
All caps

5. All SQL statements contained within a script must end with a _______________ - even if they are done in SQL Developer.
UNION
Orphan
Semicolon or forward slash
SET clause of an UPDATE statement

6. FEEDBACK
Command returns the number of records returned by a query.
BETWEEN
All
DICT_COLUMNS

7. The NEXTVAL and CURRVAL pseudocolumns can be used in which of the following SQL constructs? Select all that apply.
SET clause of an UPDATE statement
VALUES clause of an INSERT statement
Correlated
Columns

8. To place a line comment in your SQL statements - you first place a // at the beginning of the line.
Parent table
The indexed column is part of an expression. In this case - consider creating a function-based index instead
Crow's foot
FALSE

9. List the reasons that a subquery could not be unnested.
Implicit conversion
Both MIN and MAX
X
Scale

10. The TIMESTAMP WITH LOCAL TIME ZONE data type allows...
Fractional seconds
The indexed column is part of an expression. In this case - consider creating a function-based index instead
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.
DICTIONARY

11. When using the data NUMBER(10 -4) there will be _______ digits following the decimal point.
Static or dynamic
ON
4
ROLLBACK

12. A _________ subquery returns a single column with a single row
SYSDATE
Both MIN and MAX
Scalar
ON

13. The COUNT function uses the __________ wildcard.
Asterisk
BETWEEN
Time zone
Recursive

14. You use the _________ keyword to add columns or constraints to a table.
V$
BETWEEN
ADD
Retrieve

15. PAGESIZE
FALSE
SET clause of an UPDATE statement
Default is 14; when you use the default - you repeat the heading every 14 rows.
Scale

16. The using clause of the ANSI join syntax always assumes an...
4000
Equijoin and identical column names
SELECT DISTINCT menu FROM restaurant
Multiple rows

17. Converting a text literal to DATE format requires the use of the...
Rounded edges
Nested
Hide data
TO_CHAR function

18. SELECT LIST of a subquery in an INSERT statement
Command returns the number of records returned by a query.
Command determines the total number of characters SQL *Plus displays in on line before beginning a new line.
Lists all objects accessible for the chosen database connection. Also lists a helpful dependencies report for accessing change impact.
SET clause of an UPDATE statement

19. When returning multiple rows - a subquery must contain the _____ - _____ - _____ - or ______ operator - otherwise Oracle will return an error
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)
DD-MON-YY
IN ANY ALL SOME

20. The focus of the logical data model is _____________
All caps
VALUES
Mathematical equations
Business problems

21. When column names on the tables are different - you use the ______ condition.
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
Groups
ON
LENGTH

22. The _______ operator determines common rows.
Self-joins
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
SET clause of an UPDATE statement

23. 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.
Equijoin
Surrogate
Equijoin and correlated subquery
RIGHT LEFT JOIN

24. Which operator is most commonly used?
Command determines the total number of characters SQL *Plus displays in on line before beginning a new line.
FALSE
Nested
UNION

25. SQL Developer provides an extensive list of useful reports and offers the capability to create your own...
User-defined reports
X
All caps
LIKE

26. A calculation with a null always yields...
User-defined reports
Semicolon or forward slash
Another null
KEEP INDEX

27. The _____________ clause determines how rows are grouped.
GROUP BY
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.
NATURAL JOIN
Black

28. When disabling a unique or primary key - you can keep the index if you specify the __________________ clause in the ALTER TABLE statement.
Month ddth - yyyy
ANSI
KEEP INDEX
Fractional seconds

29. Joins involving multiple columns must always follow the ____________ relationship path.
Groups
Primary key/foreign key
DESC dict;
Recursive

30. 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.
Month ddth - yyyy
Inconsistencies
Semicolon or forward slash

31. List 4 aggregate functions
DD-MON-YY
Mathematical equations
COUNT(registration_date) - AVG (capacity) - MIN (capacity) - MAX (capacity)
MINUS

32. What is the tab in SQL Developer where data dictionary view information can be found?
Lists all objects accessible for the chosen database connection. Also lists a helpful dependencies report for accessing change impact.
Details
Precision
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

33. List the different types of data dictionary views.
Has not changed the name
DICT_COLUMNS
USER_ - ALL_ - DBA_ - and V$
NATURAL JOIN

34. The __________ operator is inclusive of the two values specified.
Details
USER_ - ALL_ - DBA_ - and V$
Both MIN and MAX
BETWEEN

35. What are the main components of a ROWID?
UNION
SELECT SYSDATE+1/96 - FROM dual
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.
DROP INDEX need_to_pass_i

36. Match each of the SQL commands on the left with a verb from the list.
Control - Revoke - Define - TRUNCATE Manipulate - MERGE
SELECT SYSDATE+1/96 - FROM dual
Same
Structured Query Language

37. You use the __________ keyword to change characteristics of a column.
MODIFY
Common column value
DICTIONARY
**** 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

38. You can __________ DISTINCT and a GROUP BY clause in the same SELECT statement.
Crow's foot
Combine
Twice
Any

39. When writing the syntax for finding information on three or more tables - the parenthesis around the ON clause is...
MODIFY
Actual column
Optional
Any

40. NUMBER functions can be...
ANY
Three
Nested
RIGHT LEFT JOIN

41. SQL Developer's ____________________ option allows you to selectively export certain rows and columns.
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
BETWEEN
Export Data

42. 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.
When the table is small (unless your business rules require you too)
+
VALUES
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.

43. Explain what a static data dictionary view is and how it is used
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.
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.
User-defined reports
A correct statement

44. The ROWID pseudocolumn is not an ________- but it acts like one.
RUN SCRIPT
4
Precision
Actual column

45. __________________ inserts the current date and time.
Twice
Asterisk
99.99
SYSDATE

46. What does the following function return? SELECT LENGTH(NULL) - FROM dual
Null
DECODE
Both MIN and MAX
Has not changed the name

47. The _______ function adds values together for a group of rows.
Asterisk
LENGTH
SUM
Fractional seconds

48. Explain how you can optimize your queries with subqueries and the main advantage of doing so.
X
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
Hide data
LIKE

49. What is the keyboard shortcut for the ROLLBACK command?
F12
Groups
Precision
Equijoin

50. 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?
Time zone
ADD
DICTIONARY
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.