Limit to Only One Row

[Glese]

I accidentally executed the following SQL query a moment ago:

 

UPDATE con SET contribution = '$contribution', category = '$contribution_category', description = '$contribution_description'

 

This updated the whole table (every single row), which taught me a lesson.

 

I would like to know is there a way to limit the query to just one single row, to avoid an updating of the whole table on big projects?

 

This happened in the development environment, so it is not a big deal and can be checked as lesson learned.

 

Quite dangerous this one.

[The Little Guy]

UPDATE con SET contribution = '$contribution', category = '$contribution_category', description = '$contribution_description' limit 1

[Glese]

So it is without an equal sign?

 

And I tried Limit = '1', which did not work for me.

 

Thanks for the tip.

[mikosiko]

just a note... even when LIMIT will work you normally should use a WHERE clause to specify exactly the scope of your sentence

[The Little Guy]

So it is without an equal sign?

 

yup, just like a select.

[fenway]

just a note... even when LIMIT will work you normally should use a WHERE clause to specify exactly the scope of your sentence

And without ORDER BY, LIMIT is basically random.

[Glese]

fenway, what do you mean by that?

 

Will it not work how I imagined it in the sense of the thread?

[trq]

You need to use a WHERE clause to tell mysql which row you want to update. While LIMIT will limit the update to a single row, without a WHERE clause you are still not defining which row should be updated.

[fenway]

fenway, what do you mean by that?

 

Will it not work how I imagined it in the sense of the thread?

I mean that you'll get an arbitrary row - the order of the rows examined by MySQL is totally arbitrary (in the sense that you can't guess what it will be).

 

if you want a particular one of the rows updated, and not others, you'll need both ORDER BY and LIMIT.