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 Nonequijoin can use the ________________ operator to construct joins that are not based on equality of values.
V$
LIKE
BETWEEN
ADD_MONTHS function

2. You can __________ DISTINCT and a GROUP BY clause in the same SELECT statement.
DICTIONARY
Combine
Leading-edge
Mathematical equations

3. What do views do that makes them so useful for security?
Another null
Null
Groups
Hide data

4. You use the __________ keyword to change characteristics of a column.
Extra spaces
Script
DICT_COLUMNS
MODIFY

5. The ______ operator compares a list of values for equivalency
Orphan
ANY
Common column value
Static or dynamic

6. _________________ relationships are always optional relationships.
CLOB
Recursive
ANSI
RUN SCRIPT

7. What is the Oracle data dictionary called that contains a set of tables and views containing the data about the database?
Retrieve
Semicolon or forward slash
ALL_OBJECTS
BETWEEN

8. Explain how Oracle treats locks when a database is being updated and needs to be viewed by other users.
Combine
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
KEEP INDEX
DECODE

9. The TRUNC function on a date without a format model truncates the timestamp to...
12:00:00 A.M
VALUES clause of an INSERT statement
Semicolon or forward slash
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

10. Subqueries can return...
Equijoin and identical column names
Multiple rows
DESC dict;
ANSI

11. Dynamic views begin with a ___________.
DESC dict;
ALL_OBJECTS
V$
DROP INDEX need_to_pass_i

12. What is the main difference between the NOT EXISTS and the NOT IN operators?
The way NULL values are treated
KEEP INDEX
STORAGE
ALL_OBJECTS

13. PAGESIZE
Time zone
RENAME just_two_more_weeks TO finally_i
ANSI
Default is 14; when you use the default - you repeat the heading every 14 rows.

14. Which format mask displays December 31st - 1999?
Month ddth - yyyy
Has not changed the name
Location of the file
Any

15. What is the command you would type into SQL*Plus if you needed to know the definition for each column of a table?
4
The indexed column is part of an expression. In this case - consider creating a function-based index instead
DICT_COLUMNS
All

16. The RTRIM function is useful for eliminating ________ in a string.
TO_CHAR function
MODIFY
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
Extra spaces

17. The data type definitions NUMBER(10) and NUMBER(10 -0) are the...
Same
4000
Default is 14; when you use the default - you repeat the heading every 14 rows.
Committed

18. What are the main components of a ROWID?
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.
DICT_COLUMNS
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.
Static or dynamic

19. When using the following data: NUMBER(10 -4) - the # 4 is called the __________.
ANSI
UNION operator
999999.9999
Scale

20. When disabling a unique or primary key - you can keep the index if you specify the __________________ clause in the ALTER TABLE statement.
CLOB
DECODE
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.
KEEP INDEX

21. The focus of the logical data model is _____________
Default is 14; when you use the default - you repeat the heading every 14 rows.
RENAME - COPY - DROP - TRUNCATE - LOCK - & COMMENT
Command returns the number of records returned by a query.
Business problems

22. When you create a report in SQL Developer all the column names must match identically the names of the columns found in the tables you are referencing.
DECODE
FALSE
Null
Fractional seconds

23. When writing the syntax for finding information on three or more tables - the parenthesis around the ON clause is...
Optional
Script
Precision
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.

24. 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?
All caps
12:00:00 A.M
DICTIONARY
DROP INDEX need_to_pass_i

25. The _____________ clause determines how rows are grouped.
GROUP BY
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 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

26. The ALTER SESSION statement can change the session's...
ANY
Precision
Time zone
X

27. Write a statement for SQL*Plus that shows the dictionary.
NATURAL JOIN
DESC dict;
SYSDATE
**** 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

28. 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.
4
Running a script file
DICT_COLUMNS
RIGHT LEFT JOIN

29. ___________ subqueries allow you to reference columns from the outer query and execute the inner query repeatedly
TO_CHAR function
Nested
Correlated
SYSDATE

30. The ROWID pseudocolumn is not an ________- but it acts like one.
SELECT DISTINCT menu FROM restaurant
COMMIT
Actual column
UNION operator

31. Write the syntax to rename index just_two_more_weeks_i to finally_i
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.
Mathematical equations
RENAME just_two_more_weeks TO finally_i
Self-joins

32. You can use the ________________ to subtract months from a given date.
ADD_MONTHS function
Parent table
DD-MON-YY
The way NULL values are treated

33. What is the most common DATE format found in SQL?
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.
BETWEEN
DD-MON-YY
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

34. It is always good practice to include the old values in the WHERE clause of UPDATE to ensure that another session or user _________________ in the meantime.
INNER JOIN
+
Columns
Has not changed the name

35. 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
Script
X
Run scripts

36. The using clause of the ANSI join syntax always assumes an...
BETWEEN
Equijoin and identical column names
Black
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

37. Write a solution that adds 20 minutes to a given date.
Running a script file
ROLLBACK
SELECT SYSDATE+1/96 - FROM dual
Actual column

38. When using the following data: NUMBER(10 -4) - the # 10 is called the __________.
SELECT SYSDATE+1/96 - FROM dual
VALUES clause of an INSERT statement
Black
Precision

39. A calculation with a null always yields...
Has not changed the name
Fractional seconds
Another null
Correlated

40. The ____________ clause on a CREATE TABLE statement can specify how much space to allocate.
MODIFY
STORAGE
RIGHT LEFT JOIN
X

41. When you have issued a DELETE command - you can still ________ those rows and restore the information.
VALUES
F12
Retrieve
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

42. 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.
DICT_COLUMNS
Surrogate key
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.

43. List 4 aggregate functions
SET clause of an UPDATE statement
COUNT(registration_date) - AVG (capacity) - MIN (capacity) - MAX (capacity)
Mathematical equations
Orphan

44. When column names on the tables are different - you use the ______ condition.
Combine
ON
Month ddth - yyyy
STORAGE

45. Joins involving multiple columns must always follow the ____________ relationship path.
Three
Primary key/foreign key
Run scripts
Orphan

46. Self-joins are useful for performing comparisons and checking for ___________ in data.
Recursive
Details
Inconsistencies
VALUES clause of an INSERT statement

47. How many characters can be stored in the CHAR column/field?
2000
Committed
RENAME just_two_more_weeks TO finally_i
Inconsistencies

48. An outer join includes the result rows returned by an __________ plus extra rows where no matches are found.
Business problems
VALUES
Asterisk
Equijoin

49. You use the _________ keyword to add columns or constraints to a table.
ADD
Nested
FALSE
Equijoin

50. The ________________ is a type of statement whereby you retrieve data that exists in one table - but not in another.
MINUS
Has not changed the name
Business problems
SYSDATE