/* first method  concat method */

​

select CONCAT(id+' ',name+' ' +salary) as information

from employee 

​

/* output like that

    1 ahmed 12000

*/

​

/* convert all null values */

​

select concat(employee.name ,'  ' ,employee.supervisor ) as leader

from employee

​

/* output like that

    ahmed 

*/

​

/* second method  concat_ws method 

  you can identify separtor

*/

​

select CONCAT_WS('||',name,salary)

from employee  

​

/* output like that

    mohammed||14000

*/

​