Q:

Mixture of UK and US Dates - Convert All to UK

I have just realised that after importing 8 million records into the database (long time!) that sadly some dates are mixed (UK and US format, not good!)
i.e.
26/03/2015
22/12/2014
10/08/2012
11/17/2011
11/30/2010
Not only this, the column of the database is varchar, which isnt good for performance either.
I have made a test database and I have tried this with fail:
SELECT convert(varchar, getdate(), 103)

I'm trying to get the UK dates i.e. 25/11/1992 and not 11/25/1992
Any help would be great otherwise thats a night wasted uploading data!

A:

the correct way of the select on your example is like this: 
select CONVERT(VARCHAR(10),GETDATE(),103)

But i was thinking of two solution 
make a function the take a varchar of US date and return varchar of UK date
but the big problem you don´t know if in table all the date is US type, if you can figure witch surly what type of the date you just resolved the problem, and you can put this rule on the function passing some params that help to figure that.
also you don´t need to import all the data again, after you make the above things just make an update statement of the current table using the function.
good luck. 

