[RESOLVED] Are there any results

[Piranha]

In a select-statement I need to get only if there are any responses, not what the responses are. It is to ensure that I don't insert or update anything wrong. Simply I need something simular to TRUE or FALSE, telling me if the statement did return anything or not. I have looked at the methods below:

SELECT count(id) FROM test WHERE name = 'kalle';

SELECT id FROM test WHERE name = 'kalle';

SELECT first(id) FROM test WHERE name = 'kalle';

The first and second options have to go through the whole database before returning anything. The third seems to be good, but of course I get a result back. It is of course a possibility, but is there anything that is better (as in takes less time to execute or less time to handle in PHP)?

[mjax]

The EXISTS() function is your friend. For instance:

SELECT
  *
FROM
  books
WHERE
  EXISTS (SELECT * FROM book_sales WHERE book_id = books.id)

[nnichols]

If you add an index to your "name" field the speed should not be an issue whichever of the queries you use. The fastest will be -

SELECT COUNT(*) FROM test WHERE name = 'kalle';

as it won't need to access the table file at all.

[Piranha]

Ty for your answers guys. I'll mark it as resolved since I got the answers I needed.