Doubt on update

Question

I have 3 tables. Those are shops, salepoint and storagepoint.
Salepoint and storagepoint both the tables contain doorNumber and village.
Based on the salepoint’s doorNumber and village I have selected the record for update.
The following is the query.
select a.shop_id
                   , a.shop_name,
                     a.propraitor_name,
                     a.license_number,
                     a.address,
                     b.salepoint_id,
                     b.door_number,
                     b.village,
                     c.storagepoint_id,
                     c.door_number as strgDoorNo,
                     c.village as strgVillage
               from shops a,
                      salepoint b,
                      storagepoint c
               where a.shop_id=b.shop_id
                          and
                b.shop_id=c.shop_id
                        and
                b.compare_string=? and b.village=?Now the record is displayed for updation(in the update form) . compare_string is nothing but doorNumber.
Now when I click on update button the system checks whether the salepoint doorNumber already existing or not. The salepoint doorNumber should not exist in the salepoint neighter in the storagepoint.
The following is the query for checking
select a.shop_name,
                    a.propraitor_name,
                    a.license_number,
                    a.address,
                    b.door_number,
                    b.village,
                    c.door_number as strgDoorNo,
                    c.village as strgVillage
                from shops a,
                       salepoint b,
                       storagepoint c
               where a.shop_id=b.shop_id
                           and
               b.shop_id=c.shop_id
                           and
              ((b.compare_string = ? and b.village = ?) or (c.compare_string = ? and c.village = ?))  the above query finds a record if there is a matching door number which is there in the updation form.
please ignore the ? marks. I am sending proper values instead of ? marks. When I run the above query it is returning the same record which I selected for update.it is because in that record there will be the matching salepoint door number My query should not return the same record. It should return any other record(if there is a matching salepoint door number) other than the record that is selected for update . how do i achieve this?
Edited by: Muralidhar on Apr 2, 2012 5:33 PM
Edited by: Muralidhar on Apr 3, 2012 10:04 AM

Answer 1

First of all, I don't know how anyone can think clearly about code written like that without any formatting. The first thing I would do would be to format the two queries so I could see what they are doing, e.g:
select sh.shop_id
     , sh.shop_name
     , sh.propraitor_name
     , sh.license_number
     , sh.address
     , sa.salepoint_id
     , sa.door_number
     , sa.village
     , st.storagepoint_id
     , st.door_number     as strgdoorno
     , st.village         as strgvillage
from   salepoint    sa
     , shops        sh
     , storagepoint st
where  sa.compare_string = ?
and    sa.village = ?
and    sh.shop_id = sa.shop_id
and    st.shop_id = sa.shop_id;
select sh.shop_name
     , sh.propraitor_name
     , sh.license_number
     , sh.address
     , sa.door_number
     , sa.village
     , st.door_number     as strgdoorno
     , st.village         as strgvillage
from   salepoint    sa
     , shops        sh
     , storagepoint st
where  (    (sa.compare_string = ? and sa.village = ?)
        or  (st.compare_string = ? and st.village = ?) )
and    sh.shop_id = sa.shop_id
and    st.shop_id = sa.shop_id;Now if I understand your question you want a version of the second query that returns all rows not matched by the second query. Isn't that just
where  not
       (    (sa.compare_string = ? and sa.village = ?)
        or  (st.compare_string = ? and st.village = ?) )(That's a bit of a guess though as I'm not sure I understood the question.)