set VS. select...difference?

[karen4201]

what's the difference in SQL Server for these two statements?

set @a = 'hello'

select @a = 'hello'


they seem to have the same result...so what's the difference?

 

[DotNetGnat]

Try this and see the difference...

Set @a= myfield from mytable
Select @a= myfield from mytable

-DNG

 

[JohnDTampaBay]

With regard to variables, SET can only be used to assign a value to a single variable. SELECT can be used to assign values to multiple variables. SELECT can pull value(s) from database table(s); SET cannot.

--John
-----------------------------------
Behold! As a wild ass in the desert
go forth I to do my work.
--Gurnie Hallock (Dune)

 

[karen4201]

Thanks for the info.

Is there any speed or memory issues that would suggest using one approach over the other?

 

[JohnDTampaBay]

SELECTing from database table(s) will take more resources because of data access. Other than that, there is no resource difference in the two statements.

--John
-----------------------------------
Behold! As a wild ass in the desert
go forth I to do my work.
--Gurnie Hallock (Dune)