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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', 480);

                     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:
                 •  WHERE specifies the criteria according to which rows are retrieved.
                 •  ORDER BY specifies an order (Ascending or Descending) to return the rows.



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