> select main_table.*
> (select first 1 second_table.some_field from second_table where second_table.field = main_table.filed) as check_field
> (select first 1 third_table.some_field from third_table where third.field = check_fild) as check_field2
> from main_table
>
> i know that this kind of solution works on sysbase and it's really make easier to do it.....
>
> Please tell mi that this is also posslible with firebird, a have 2.1.1
> version on window xp sp3, and pleas tell mi how to do it....

Why do you use such strange syntax at all? Don't Sybase have JOINs?

select main_table.*, second_table.some_field as check_field,
third_table.some_field as check_field2
from main_table
left join second_table on second_table.field = main_table.filed
left join third_table on third.field=second_table.some_field

SY, SD.