>>Hi all
>>
>>I have a piece of SQL that really needs to be performed quicker, I have 2 tables:
>>
>>Person
>>Referral
>>
>>Person has a date of birth and I am fetching all persons who were under 18 on their first referral, here is the SQL:
>>
>>
>>select *;
>> from person p
>> inner join referral r on p.cl_ref = r.cl_ref and !empty(r.re_date);
>> where gomonth(p.cl_dob, 216) > (select min(rr.re_date) from referral rr;
>> where rr.cl_ref = p.cl_ref and !empty(rr.re_date))
>>
>>
>>According to Fox none of this is optimised, both cl_ref fields on each table are indexed.
>>
>>Can anyone suggest an alternative that may be quicker - or is there anything else I could do to speed up the query?
>>
>>Thanks
>>Kev
>
>
>SELECT P.*,r.*;
> FROM;
> FORCE (select cl_ref , min(re_date) re_date from referral rr WHERE re_date<>{} GROUP BY 1) X;
> JOIN person p ON p.cl_ref=x.cl_ref AND gomonth(p.cl_dob, 216) > x.re_date;
> JOIN referral r on r.cl_ref = p.cl_ref ;
> WHERE {} <> r.re_date
>* or
>
>SELECT P.*,r.*;
> FROM;
> FORCE (select cl_ref , min(re_date) re_date from referral rr WHERE re_date<>{} GROUP BY 1) X;
> JOIN person p ON p.cl_ref=x.cl_ref AND gomonth(p.cl_dob, 216) > x.re_date;
> JOIN referral r on r.cl_ref = p.cl_ref ;
> HAVING r.re_date <> {}
>
Same performance when I try both of these....