Join the social network of Tech Nerds, increase skill rank, get work, manage projects...
 
  • What is the use of UPDATE statement in MySQL?

    • 0
    • 1
    • 0
    • 1
    • 0
    • 0
    • 0
    • 0
    • 108
    Comment on it

    In MySQL, the UPDATE statement is used to update existing records in a table.

    UPDATE Syntax

    UPDATE table_name
    SET column1=value1,column2=value2,...
    WHERE some_column=some_value;
    

    In the above syntax, WHERE clause specifies which row or rows will be updated,if we don't define WERE clause then all records of the table will be updated.

    We have a table "employee" as below:

        employee
    
        id  first_name               salary       country
        .......................................................
        1   John                     10000         Canada
        2   Chris                    20000         Canada
        3   Max                      30000         Korea
        4   Jenny                    25000         Canada
    

    UPDATE Example

    The below statement will update "country" for the employee "John" in the "employee" table:

    UPDATE employee
    SET country='London', salary='15000'
    WHERE first_name='John';
    

    Result

        id  first_name               salary       country
        .......................................................
        1   John                     15000         London
        2   Chris                    20000         Canada
        3   Max                      30000         Korea
        4   Jenny                    25000         Canada
    

    If we remove the WHERE clause from the above statement as below then all the records in the table "employee" table will be updated

    UPDATE employee
    SET country='London', salary='15000';
    

    Result

        id  first_name               salary       country
        .......................................................
        1   John                     15000         London
        2   Chris                    15000         London
        3   Max                      15000         London
        4   Jenny                    15000         London
    

    Hope this will help you :)

 0 Comment(s)

Sign In
                           OR                           
                           OR                           
Register

Sign up using

                           OR                           
Forgot Password
Fill out the form below and instructions to reset your password will be emailed to you:
Reset Password
Fill out the form below and reset your password: