Adding a new column with data

Below is my table:

Id  Name    City    Managerid  
------------------------------
1   Shawn   NYC     3
2   Kevin   Mumbai  4
3   Ryan    Mumbai  1
4   Kanye   SF      1

Now I want to add a new column called ‘Gender’ with values M,M,M,F in 4 rows respectively.

I first added a new column using:

alter table employee add gender varchar(50)

Now I understand I can add data one by one by using:

update employee 
set gender = 'M' 
where id = 1

But how do I add all 4 data at once?

Answer

You don’t, unless there is some other piece of relational data that allows the engine to group the rows in someway. For example if all the males were in Mumbai. Alternatively, you can do it in 2 statements.

update employee set gender= 'M' where id IN (1, 2, 3)
update employee set gender= 'F' where id IN (4)

But this is still not useful if you have a large number of males and females that need to be updated after adding the column.