SQL Server String Manipulation for URLs?

I need to append a paramter-value 'xval=9' to all non-blank SQL server column values in a multi-million row table. The column contains URLs and they have a random amount of "querystring" parameters appended to the column. So when I append, I may need to append '?xval=9' or I may need to append '&val=9', depending on if parameters already exist.

So the URL values could like like any of these:

http://example.com/example
http://example.com/example/?aval=1
http://example.com/example/?aval=1&bval=2
http://example.com/example/index.html?aval=1&bval=2

'aval' and 'bval' are just samples, really any kind of key/value pair might be on the end of the URL.

What is the smartest pure-TSQL way to manipulate that, hopefully utilizing some kind of indexing?开发者_JS百科

Thanks.

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Do that on Presentation or Model layer, not on Data layer.

i.e. read all data and manipulate using C# or other language you use.

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Maybe this should work

SELECT CASE CHARINDEX('?', Url) WHEN 0 THEN Url+'?foo=boo' ELSE Url+'&foo=boo' END AS Url FROM Whatever