The simplest way to add ENo 1, ENo 2, ENo 3 into the rows of the table is to use a ROW_NUMBER() type function. In SQL Server, it looks like:
ROW_NUMBER() OVER (ORDER BY column_name ASC) AS description
And you can use it in your query like:
SELECT 'ENo ' + ROW_NUMBER() OVER (ORDER BY itemname ASC) AS rowid, itemname, itemvalue
In MySQL, you have to put this in a stored procedure and use:
set @i = 0;
select CONCAT('ENo ', @i:=@i+1) as rowid, itemname, itemvalue from mytable;
If you want to have random names in that column instead of numbers (ie: machine15, machine 22, machine 19 or east unit, west unit, south unit), you will need to do this with a python script that takes in the raw data set and creates a new one.