Here is a split function, it can apply as dbo.Split(\'sf,we,fs,we\',\',\'), when I change the string to column name it doesn\'t work, such as dbo.Split(table.
dbo.Split(\'sf,we,fs,we\',\',\')
dbo.Split(table.
That is because the function is returning a TABLE.
SELECT Split(myColumn) FROM myTable
will mean
SELECT myOutputTableFromSplit FROM myTable
It means, return a table from the table & SQL cannot do that.