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column_nameN data_type (size)
);
While creating a table in SQL, it is necessary to give a data type for each field/column. Let us
create a table named Student having StudentId, FirstName, LastName, and Marks fields in the
following way:
CREATE TABLE Student
(
StudentID INTEGER,
FirstName CHAR(30),
LastName CHAR(30),
Marks INT
);
In the preceding code, you have noticed that a value 30 is given with the CHAR data type
within the parenthesis as its size. The meaning of 30 is that you can store a string value upto
30 characters in the FirstName and LastName fields. Whether you store a single character or 30
characters, this field will occupy space required for 30 characters. If you store one character, 29
blank spaces will be inserted with the character.
INSERTING RECORDS IN A TABLE
After creating a table, you can insert records into it by using the INSERT command. The syntax to
insert a record into a table is:
INSERT INTO table_name
VALUES ('val_column1', 'val_column2', ... , 'val_columnN');
Let us insert the following records in the Student table:
StudentID FirstName LastName Marks
10001 Amit Sharma 450
10002 Divya Kaushik 480
10003 Aadarsh Kumar 475
To insert above records, we use the following commands:
INSERT INTO Student VALUES (10001, 'Amit', 'Sharma', 450);
INSERT INTO Student VALUES (10002, 'Divya', 'Kaushik', 480);
INSERT INTO Student VALUES (10003, 'Aadarsh', 'Kumar', 475);
RETRIEVING RECORDS FROM TABLE
The SELECT command retrieves zero or more rows from a table. It helps us join information from
different tables and filter specific information as per the required criteria. The SELECT command
is the most useful DML command. The ‘SELECT’ statement has many optional clauses which are
as follows:
Introduction to MySQL 151

