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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:


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