Question

I want to normalize date fields from an old badly designed db dump. I now need to update every row, where the datefield only contains the year.

update table set date = '01.01.' + date
where date like '____' and isnumeric(date) = 1 and date >= 1950

But this will not work, because sql does not do short circuit evaluation of boolean expressions. Thus I get an error “error converting nvarchar ‘01.07.1989’ to int”

Is there a way to work around this? The column also contains strings with a length of 4, which are not numbers (????, 5/96, 70/8, etc.) the table only has 60000 rows

Answer 1

You could always do a subquery

update table set date = '01.01.' + date
where id in(

   select id from table
   where date like '____' and isnumeric(date)

)
and convert(int, date) >= 1950