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 The BETWEEN operator defines the range of values that the column values must fall within to make the condition
true.
 The IN operator selects values that match any value in the given list of values.
 % and _ are two wild card characters. The percent (%) symbol is used to represent any sequence of zero or more
characters. The underscore (_) symbol is used to represent a single character.
 NULL represents a value that is unavailable, unassigned, unknown or inapplicable.
 The results of the SELECT statement can be displayed in the ascending or descending order of a single column or
columns using ORDER BY clause.
 DROP DATABASE drops all tables in the database and deletes the database. Once the DROP command is used,
then we cannot use that database. So, we should be careful with this command.
 The CREATE statement is used to create a table in MySQL with constraint. A constraint is a restriction on the
behaviour of a variable.
 INSERT query is used for inserting new rows or data into an existing table.

 The ORDER BY keyword in MySQL is used to sort the result-set in ascending or descending order.
 The ORDER BY keyword sorts the records in ascending order by default. To sort the records in descending order,
use the DESC keyword.
 An aggregate function is a function where the values of multiple rows are grouped together as input based on
certain criteria to form a single value of more significant meaning.
 The COUNT() function returns the number of rows that matches a specified criteria.
 The AVG() function returns the average value of a numeric column.
 The SUM() function returns the total sum of a numeric column.

OBJECTIVE TYPE QUESTIONS
1. Fill in the blanks.
(a) ................................ is a freely-available open-source RDBMS that implements SQL.
(b) MySQL provides a dummy table named ................................ .
(c) The ................................ keyword eliminates duplicate records from the results of a select statement.
(d) Patterns in MySQL are described using two special wild card characters such as ................................
and ................................ .
(e) The keyword ................................ is used to select rows that do not match the specified pattern of
characters.
(f) The default order of ORDER BY clause is ................................ .
(g) The ................................ function is used to count the number of records in a ……………………… column.
(h) The rows of the table (relation) are referred to as ................................ .
(i) A virtual table is called a ................................ .
(j) The non-key attribute which helps to make relationship between two tables is known as
Answers: (a) MySQL (b) dual (c) distinct
Computer Science with Python–XII 12.52 2. State whether the following statements are True or False. (i) view
................................ .
(d) % (percent), _ (Underscore) (e) NOT LIKE

(f) ascending
(g) count()
(h) tuples

(j) Foreign key

(a) (Duplication of data is known as Data Redundancy.

(b) An Attribute is a set of values of a dissimilar type of data.

(c) MySQL supports different platforms like UNIX and Windows.
(d) UPDATE TABLE command is used to create table in a database.