> Of course the real problem here is that the query is being executed
> the wrong way. I know this because you say that using a left join
> reduces it to 10 seconds.

As I understood all problem is in execution plan. Changing join to
left join efects oprimiser and it selects different execution plan?

Does anyone know good online book about optimising querys?

Thank You and all other people for replying to my question.