Creating your own Tinyurl style uid

Question

I\'m writing a small article on humanly readable alternatives to Guids/UIDs, for example those used on TinyURL for the url hashes (which are often printed in magazines, so n

Answer 1

Some time ago I did exactly this, and I followed the way Sklivvz mentioned. The whole logic was developed with a SQL server stored procedure and a couple of UDF (user defined functions). The steps were:

• say that you want to shorten this url: Creating your own Tinyurl style uid
• Insert the URL in a table
• Obtain the @@identity value of the last insert (a numeric id)
• Transform the id in a corresponding alphanumeric value, based on a "domain" of letters and numbers (I actually used this set: "0123456789abcdefghijklmnopqrstuvwxyz")
• Return that value back, something like 'cc0'

The conversion was realized thru a couple of very short UDF.

Two conversion called one after the other would return "sequential" values like these:

select dbo.FX_CONV (123456) -- returns "1f5n"

select dbo.FX_CONV (123457) -- returns "1f5o"

If you are interested I can share the UDF's code.