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1)Database is a collection of …

a)all of the above

2) DBMS stands for …

a)Database management systems

3) Phases of a database development are …

All of these

4) ER-diagrams are output from the … phase of Database Development.

a) Conceptual design

5) What do you need to consider when you make a database in SQL?

All of the above

6) The column of a table is referred to as the …

atribut

7) The another name for a row is …

Tuple

8) Through normalization data redundancy …

Good design

9) Types of update anomalies are …

Modification anomaly

Insertion anomaly

Deletion anomaly

10) A functional dependency is a relationship between or among …

Functional dependencies

11) The FD X->Y is a full dependency in a relation R, if there is _____ attribute A that can be _____ X and the dependency still holds.

No, the pk

12) The FD X->Y is a partial dependency in a relation R, if there is _____ attribute A that can be _____ X and the dependency still holds.

At least one, pk

13) Which normal form is considered as a “good design” for relational database?

3nf

14) Normalization is …

Redandancy Dependence

15) Who proposed the relational model?

Edgar F. Codd

16) A relation in which the intersection of each row and column contains one and only one value is said to be in ...

1NF

17) A table in 1NF in which the primary key consists of two or more attributes …

UNF

18) A table that satisfies 2NF …

1NF

19) For a relation to be in 2NF, ... attribute must be fully functionally dependent on ... .

No, PK

20) For a relation to be in 3NF, it should not contain ... attribute that is transitively dependent on ... .

No, PK

21) SQL stands for …

Structured Query Language)

22) DDL stands for …

data definition language (DDL)

23) DML stands for …

a data manipulation language (DML).

24) DDL is used to …

defines constructs that structure the data in the database

25) Which of the SQL statements can be used to create a table?

Create table

26) DDL commands are …

Create, drop alter, rename, comment , truncate

27) What SQL structure is used to limit column values of a table?

check constraints

28) Which column properties specifies whether or not cells in a column must contain a data value?

No NULL constrraints

29) Unique constraint is used to …

ensure that values in columns are unique.

30) Numeric data types are …

• Numeric (integers, floating points, etc)

• Character strings (char, varchar, etc)

• Bit strings (bit, blob, etc)

• Temporal Data (date, time, timezone, timestamp, etc)

• Boolean Data (true, false)

31) The statement in SQL which allows to change the definition of a table is …

Alter table

32) What SQL command can be used to delete columns from a table?

Drop table (alter table TABLE_NAME drop column column_name)

38) The command to eliminate a table from a database is …

Drop table

39) Data Manipulation Language is used for

insertion, modification, deletion, retrieval of information

40) The command to add a row in a table is …

Insert

41) Which SQL statement is used to update data in a database?

Update

42) In which of the SQL statements is the keyword SET used?

update table set attribute=value where condition

43) The command to remove rows from a table is …

Delete

44) The result of a SQL SELECT statement is a(n) …

Table

45) Which SQL statement is used to extract data from a database?

Select

46) What does follow after the SQL SELECT clause?

SELECT FROM WHERE

47) What does the SQL FROM clause do?

From table

48) Which SQL keyword is used to specify conditional search?

Where

49) What does follow after the SQL WHERE clause?

Seceltion condition

50) Correct order of keywords for SQL SELECT statements is …

Select from where

51) Relational algebra is …

is providing a theoretical foundation for relational databases. 

52) Operations of relational algebra are

Min, Max, count, AVG, SUM

53) Projection selects …

PI(Greek)

54) The symbol for selection is …

Sigma(Greek(paint))

55) Selection selects …

Parenthesis

56) In an SQL SELECT statement querying a single table, the asterisk (*) means that …

Select from a table.

57) Join operation …

The join operation enables querying information from two or more related tables.

The most common form of a join is an equi-join. An equi-join combines two or more tables based on the tables’ primary and foreign keys.

58) Different types of JOIN command

INNER JOIN

OUTER JOIN:

• LEFT JOIN

• RIGHT JOIN

• FULL JOIN

CROSS JOIN

59) What type of join is needed when you wish to include rows that do not have matching values?

OUTER JOIN

60) Union is …

Union (R1 U R2) is the relation containing all tuples that appear in R1, R2, or both.

62) Intersection is …

Intersection (R1 ∩ R2) is the relation containing all tuples that appear in both R1 and R2.

63) Set difference is …

Set difference (R1 - R2) is the relation containing all tuples of R1 that do not appear in R2.

64) Union-compatible …

Two tables must be union-compatible for the union operation to work.

• They need to have same number of attributes (columns)

• The domain of each attribute must also be the same.

65) What is the purpose of the SQL AS clause?

As clause ( long answer)Rename Alisher Aitty

66) Which SQL statement is used to return only different (unique) values?

Select Dist

67) The NULL SQL keyword is used to ...

I NULL is a special value that is valid for all domains.

NULL indicates absence of a value in a column.

Since NULL may appear in a column, we must be able to detect its presence.

68) The SQL BETWEEN operator …

For ranges

69) Choose the correct keyword for a range condition

Between

70) What keyword can you use to search for a string in a column?

Like

71) LIKE operator uses … and … .

% _

72) SQL aggregate functions are …

• Min() selects the minimum value.

• Max() selects the maximum value.

• Avg() selects the average value.

• Count() selects the number of occurrences.

• Sum() selects the sum of occurrences.

73) Which SQL functions is used to count the number of rows in a SQL query?

Count(*)

74) The AVG SQL function returns the ...

average value.

75) What keyword would you use to group your results by a column's values?

Group By

76) The HAVING clause …

filtering groups

77) Which SQL keyword is used to sort the result set?

Order By

78) When sorting your results by a column's values that are integers, what keyword would you use to sort from greatest to least

DESC.

79) A subquery in an SQL SELECT statement is enclosed in …

Nested Query

80) Can you use the INSERT and SELECT clauses in one SQL statement?

YES, True

81) The IN and NOT IN operators can be used to …

Test simple set membership . used in subqueryes

82) A view is …

A view (“представление”, “вид”) is a table, derived from one or more defining tables.

83) For what purposes are views used?

Views can represent a subset of the data contained in a table.

84) What is a transaction?

A transaction is a sequence of database statements that needs to execute atomically, as a whole, in order to maintain database consistency.

85) Which of the following command makes the updates performed by the transaction permanent in the database?

Atomicity 

86) The effect of the ROLLBACK command in a transaction is

is used to discard the updates of a transaction

87) Isolation levels are …

The isolation level of a transaction determines what data the transaction can see when other transactions are running concurrently

88) The most strict level of isolation is …

serializable

89) TCL stands for …

TCL (Transaction Control Language)

90) DCL stands for

DCL (Data Control Language)

91) A DBA is …

A database administrator (DBA) is the “super-user” of a database.

92) Privileges of a DBA are

A DBA can create users and grant users different privileges.

93) Commands of Data Control Language are…

Grant Revoke

94) In SQL GRANT command is used to …

We can grant privileges to users using the grant command

95) In SQL REVOKE command is used to

We may also revoke privileges from a user using the REVOKE command

The revoke command takes the same form as the grant command. That is,

REVOKE privilege list ON table FROM user;

So, if we wanted to remove the delete privilege from vinny on the member table, we would write:

REVOKE delete ON member FROM vinny;

96) Choose the command to create a new user

Create User;