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. The data type definitions NUMBER(10) and NUMBER(10 -0) are the...
All caps
Same
Asterisk
Export Data

2. Match each of the SQL commands on the left with a verb from the list.
Control - Revoke - Define - TRUNCATE Manipulate - MERGE
STORAGE
Self-joins
ADD_MONTHS function

3. What is Oracle's most popular index storage structure?
B-Tree Index
Semicolon or forward slash
FALSE
Combine

4. To restart a sequence at a lower number - you can drop and ________ the sequence.
Scale
CLOB
Re-create
A correct statement

5. When writing the syntax for finding information on three or more tables - the parenthesis around the ON clause is...
Optional
Precision
Equijoin and identical column names
Combine

6. A _________ subquery returns a single column with a single row
Primary key/foreign key
Another null
Control - Revoke - Define - TRUNCATE Manipulate - MERGE
Scalar

7. Explain how Oracle treats locks when a database is being updated and needs to be viewed by other users.
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
All caps
Has not changed the name
Any

8. The purpose of the HAVING clause is to eliminate___________.
All
Any
COMMIT
Groups

9. List 4 aggregate functions
DECODE
SYSDATE
COUNT(registration_date) - AVG (capacity) - MIN (capacity) - MAX (capacity)
Has not changed the name

10. 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.
FALSE
The way NULL values are treated
Black

11. NUMBER functions can be...
Nested
GROUP BY
F12
Month ddth - yyyy

12. FEEDBACK
Columns
Leading-edge
Command returns the number of records returned by a query.
Parent table

13. What does the following function return? SELECT LENGTH(NULL) - FROM dual
VALUES
Null
Inconsistencies
Asterisk

14. An outer join includes the result rows returned by an __________ plus extra rows where no matches are found.
UNION operator
Multiple rows
Structured Query Language
Equijoin

15. What is the command you would type into SQL*Plus if you needed to know the definition for each column of a table?
DICT_COLUMNS
Equijoin and correlated subquery
LIKE
Primary key/foreign key

16. The ____________ icon allows you to execute multiple statements and emulates SQL *Plus as much as possible.
ANSI
Surrogate
RUN SCRIPT
Null

17. Returns rows if the condition is true for all the values in the list
FALSE
Run scripts
All
Month ddth - yyyy

18. Explain in detail the impact of INDEXES and how they are used by Oracle.
Orphan
The indexed column is part of an expression. In this case - consider creating a function-based index instead
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
DROP INDEX need_to_pass_i

19. The COUNT function is useful for determining whether a table has...
User-defined reports
MODIFY
**** 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
Data

20. Which one of the following string functions tells you how many characters are in a string?
Groups
Nested
LENGTH
DECODE

21. You can use the ________________ to subtract months from a given date.
X
ADD_MONTHS function
SET clause of an UPDATE statement
SELECT DISTINCT menu FROM restaurant

22. You can __________ DISTINCT and a GROUP BY clause in the same SELECT statement.
Combine
Data
SELECT DISTINCT menu FROM restaurant
ON

23. A transaction is a...
FALSE
Logical unit of work
Actual column
Details

24. You use the _________ keyword to add columns or constraints to a table.
All caps
Run scripts
DROP INDEX need_to_pass_i
ADD

25. Joins involving multiple columns must always follow the ____________ relationship path.
X
DICTIONARY
X
Primary key/foreign key

26. Which operator is most commonly used?
Rounded edges
ANY
STORAGE
UNION

27. When using the following data: NUMBER(10 -4) - the # 4 is called the __________.
KEEP INDEX
Scale
Equijoin and correlated subquery
@ or START

28. Checks whether any value in the list makes the condition true.
User-defined reports
Any
BETWEEN
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.

29. SELECT * FROM instructor ORDER BY phone
A correct statement
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.
Multiple rows
INTERSECT

30. Queries that are found in parentheses are done first - just as in the order of operations when doing...
All caps
Re-create
Mathematical equations
Extra spaces

31. 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.
DICTIONARY
Retrieve
Optional
RIGHT LEFT JOIN

32. Write an SQL statement for SQL *Plus in which you want any unique menu items to be displayed from the restaurant table
Any
Multiple rows
SELECT DISTINCT menu FROM restaurant
Command returns the number of records returned by a query.

33. The same function can be used ______ in a SELECT statement.
Twice
B-Tree Index
X
Command determines the total number of characters SQL *Plus displays in on line before beginning a new line.

34. What is the tab in SQL Developer where data dictionary view information can be found?
Details
Equijoin
B-Tree Index
Primary key/foreign key

35. The ___________ operator tests whether a matching row cannot be found.
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
CLOB
Another null

36. Information that is returned after you run your statement are found in the __________ tab in SQL Developer.
SELECT SYSDATE+1/96 - FROM dual
DECODE
Results
Any

37. The ____________ clause on a CREATE TABLE statement can specify how much space to allocate.
Non-matching rows
4000
UNION operator
STORAGE

38. Oracle uses the outer join operator to indicate that nulls are shown for...
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.
INTERSECT
RENAME just_two_more_weeks TO finally_i
Non-matching rows

39. The term ____________ ___________ is used to express a join that satisfies the join condition.
INNER JOIN
Twice
Re-create
VALUES

40. In SQL Developer field names and table names are shown in the color _______.
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
Running a script file
Black
X

41. Write a statement for SQL*Plus that shows the dictionary.
Crow's foot
**** 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
RUN SCRIPT
DESC dict;

42. 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?
DICTIONARY
Data
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
ADD_MONTHS function

43. What does SQL stand for?
SELECT DISTINCT menu FROM restaurant
Time zone
Structured Query Language
Business problems

44. When using the data NUMBER(10 -4) there will be _______ digits following the decimal point.
4
Control - Revoke - Define - TRUNCATE Manipulate - MERGE
Run scripts
Retrieve

45. The TRUNC function on a date without a format model truncates the timestamp to...
Mathematical equations
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
LIKE
12:00:00 A.M

46. What is the data type you can use if you need an unlimited number of textual characters?
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.
SET clause of an UPDATE statement
DICT_COLUMNS
CLOB

47. When using the following data: NUMBER(10 -4) - the lowest number you can possibly have is __________.
UTC
999999.9999
Command returns the number of records returned by a query.
**** 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

48. What is the Oracle data dictionary called that contains a set of tables and views containing the data about the database?
Details
ALL_OBJECTS
4000
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.

49. You use the __________ keyword to change characteristics of a column.
MODIFY
4
Structured Query Language
12:00:00 A.M

50. How many characters can you have using the VARCHAR data type?
Testing functions
4000
Implicit conversion
UNION