Fixing faulty dates - select on day part of a date field

Hi all,

I've got a problem with dates on one of my tables. I've been inserting dates 
in the format 'dd/mm/ccyy' which for the days 13-31 for each month worked 
fine.

The problem I have is that for the days 01-12 for each month, the date was 
interpretted as 'mm/dd/ccyy'.  Now I know about it I need to fix it.

Two questions.

1) how can I select on part of a date?  I need to select all records where 
the day is not > 12.
2) can I do this in a single update, i.e. can I do something around

update calls set xdate =  ???? where ??????;

-- 
Gary Stainburn
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