For a long, long time, users of SQL Server had requested some way to split a string. That's a common need when working with rows from comma-delimited files (CSVs).
In the example below, I've asked it to break up the string 'Greg,Tom',Sandra' whenever it finds a comma. Notice I could use another delimiter like TAB or semicolon instead.
The values returned are in a table. This is a table-valued function.
The downside of this function is that it doesn't promise to return the rows in order (as tables don't have a default order), and it doesn't return a column that lets us know what order the columns were in. So it can be a bit awkward to work with.
If you want a function that works better than this, in our free SDU Tools for Developers and DBAs, we have a SplitStringByDelimiter function that does just that. I suggest you take a look at it.
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