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    For example, to find the StudentID and FirstName where Age is 16 and FirstName is ‘Saanvi’, use   To remove all records from a table, use the following command:
     the following SELECT command:   DELETE FROM Students;

                                 In MySQL, you can exit from a database by using the EXIT or QUIT commands.

                                                                                                21 st   #Critical Thinking
                          INTERDISCIPLINARY LEARNING                                          Century   #Information Literacy
                                                                                               Skills
     Ask
     AGENT             In science class, you are recording daily temperatures to study climate change. Complete the given tasks:
     OrangeAI
     Create a Students table in the school database with the fields ID, Name, Class, Percentage and City.
     Then, find the students who have a percentage above 80.  (a)  Create a table named WeatherData with fields: Date, City, Minimum and Maximum Temperature.
                       (b)  Insert the temperature data for your city for a week.

     Study             (c)  Write SQL queries to show all data when the maximum temperature is above 38°C.
                       (d)  Write SQL queries to show all data when the minimum temperature is above 24°C.

     UPDATING RECORDS IN A TABLE

     To modify  existing  records in a table,  use  the UPDATE command.  The basic  syntax  for  the     TECH
     UPDATE command is as follows:   T   ¢   ANSI SQL standard: A set of rules defined by the American National Standards Institute
                        E           to ensure consistency and compatibility of SQL across different database systems.
     UPDATE table_name SET Column = value WHERE condition;   R
                       M
     To change the LastName and Address of the student having 32 as StudentID, use the following   S  ¢   PRIMARY KEY: A field used to uniquely identify records in a database.
     command:                   ¢   FOREIGN KEY: A field in a table that refers to the primary key in another table.

                     REWIND RUN

                     «   Data includes raw facts, figures or symbols that are yet to be processed into meaningful information.
                     «   A database is defined as an organised collection of data that is stored and accessed electronically.
     DELETING RECORDS FROM A TABLE  «   A relational database is a type of database that stores data in the form of tables.

     The DELETE command is used to remove records from a table. It can be used in two ways:   «   A key is a column or a set of columns that helps us to identify records in a table.
                     «   SQL enables us to store, retrieve and manipulate data in the form of tables.
       Without WHERE clause          With the WHERE clause
                     «   A data type defines the sort of value that a column will contain.
     A specific  record can be  removed  using  the  WHERE clause  with the  DELETE command.  If  the     «   SQL operators are used to perform operations on values in an SQL query.

     DELETE command is used without the WHERE clause, all the records in the table will be removed.   «   SQL constraints are used to define rules for table data.
     Here is the command to remove the record of a student whose FirstName is Dev:

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                                                                                              MySQL: My First Database

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