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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:






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