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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 INT,
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 data from one or more tables in a database. It allows you to fetch
zero or more rows based on specific criteria. It helps us to 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:
Techipedia (MySQL) 175

