How to truncate string using SQL server

If you only want to return a few characters of your long string, you can use:

select 
  left(col, 15) + '...' col
from yourtable

See SQL Fiddle with Demo.

This will return the first 15 characters of the string and then concatenates the ... to the end of it.

If you want to to make sure than strings less than 15 do not get the ... then you can use:

select 
  case 
    when len(col)>15
    then left(col, 15) + '...' 
    else col end col
from yourtable

See SQL Fiddle with Demo