SQLSERVER Functions- Coalesce()

SQL Server  built-in functions

Coalesce()

It is A function Is Very Much Useful at Run time When We Have Multi Value Attribute in a Table.

If U Consider below facts placed in a employee table With Id, Name, ph_no, Alt_no, Office no.

id	Name	Ph_ no	Alt_ no	Office no
101	Albert	999999	456453	321333
102	khan	null	null	123455
103	victor	112121	null	null
104	lovely	null	null	1897321

Above Employee table may have single value are three values if it have single value then it fill null  values with remaining attributes

When We Retrieve The Number from employee table That Number Should Not be Null value To get not null value from employee table We Use Coalesce() Function It Returns First Encountered Not Null Value  from employee table

select id , name ,coalesce(Ph_no,Alt_no,Office_no) as contact number from employee

 it returns

id	Name	Contact number
101	Albert	999999
102	khan	123455
103	victor	112121
104	lovely	1897321

Thank you CodeProject