If you want to update just the first record and it’s not possible to work with specialized conditions within the where clause in MySQL you can do this:

update table set field=1 limit 0,1

But limit won’t work with T-SQL - what to do? Idea: Use top. Normally top used within select-statements:

select top 5 from table

But using this in an update results in a syntax-error:

update top 1 table set field=1

You have to change the top-syntax to top(n) and it works:

update top(1) table set field=1