Standardizing dates in SQL. Arithmetic overflow - sql-server-2005

Question

I have a string field dob which has birthdates in various formats e.g.
dob
July 1, 1945
1967-1-7
13 May 1956
8 May 1947
27 September 1953
1952-3-25
I have attempted to use MS SQL 2005 to create a standardized date field
select convert(datetime,dob,103)
from myTable
I get an arithmetic overflow which appears to be associated with the last value, presumably because it is trying to convert the 25 to a month when it is a day
I have tried
setting the language to british and various other styles without success
Any suggestions?

Answer 1

Why would you attempt to store it in a given format? Can you not just store it as a datetime type? The biggest advantage to storing it in a locale independent is that you can offload the presentation logic to the UI where it belongs. Plus, you can avoid messy situations where you have a DOB of 3-4-5 (2003 April 5th, March 4th 2005, 3rd April 2005).
Conversion to a datetime works just fine for me (US locale).
; with myTable (dob)as
(
select 'July 1, 1945'
UNION ALL SELECT '1967-1-7'
UNION ALL SELECT '13 May 1956'
UNION ALL SELECT '8 may 1947'
UNION ALL SELECT '27 september 1953'
UNION ALL SELECT '1952-3-25'
)
SELECT
cast(T.dob AS datetime) AS real_datetime
, T.dob
FROM
myTable T
Results
real_datetime dob
1945-07-01 00:00:00.000 July 1, 1945
1967-01-07 00:00:00.000 1967-1-7
1956-05-13 00:00:00.000 13 May 1956
1947-05-08 00:00:00.000 8 may 1947
1953-09-27 00:00:00.000 27 september 1953
1952-03-25 00:00:00.000 1952-3-25