How to parse a string and create several columns from it?

Question

I have a varchar(max) field containing Name Value pairs, in every line I have Name UnderScore Value.

I need to do a query against it so that it returns

Answer 1

SELECT substring(NameValue, 1, charindex('_', NameValue)-1) AS Names, 
  substring(NameValue, charindex('_', NameValue)+1, LEN(NameValue)) AS Values
FROM Table

EDIT: Something like this put in a function or stored procedure combined with a temp table should work for more than one line, depending on the line delimiter you should also remove CHAR(13) before you start:

DECLARE @helper varchar(512)
DECLARE @current varchar(512)
SET @helper = NAMEVALUE
WHILE CHARINDEX(CHAR(10), @helper) > 0 BEGIN
    SET @current = SUBSTRING(@helper, 1, CHARINDEX(CHAR(10), NAMEVALUE)-1)
    SELECT SUBSTRING(@current, 1, CHARINDEX('_', @current)-1) AS Names, 
      SUBSTRING(@current, CHARINDEX('_', @current)+1, LEN(@current)) AS Names
    SET @helper = SUBSTRING(@helper, CHARINDEX(CHAR(10), @helper)+1, LEN(@helper))
END
SELECT SUBSTRING(@helper, 1, CHARINDEX('_', @helper)-1) AS Names, 
  SUBSTRING(@helper, CHARINDEX('_', @helper)+1, LEN(@helper)) AS Names