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MySQL stored procedure: IF WHERE

I am trying to select some data as follows:

SELECT column
FROM table
WHERE a = a1
AND (b = b1 OR b = b2 OR b = b3);

I want this to be, if b is not equal to b1, check b = b2. However, if b = b1, do not check other conditions. The result of this select statement should be only one record. However, I do not have in the statement, it checks all three conditions and sometimes returns several lines. Again, I would like him to stop checking if the condition is true.

Any ideas on how this can be implemented? I tried the case, but it did not work ...

Thank you in advance!

EDIT Here is the actual query I'm trying to run.

INSERT INTO shipment_flights 
    (airlinename, flt_no, flt_date, destination, phone, depttime, arrivaltime, pcs, weight)
SELECT st.airlinename, flightno, flightdate, destination,     
(SELECT phone 
FROM carrierlocations 
WHERE carriers_carrierid = (select carrierid from carriers where airlinename = st.airlinename) 
AND (city = destination OR (city != destination AND
    city = (SELECT city FROM airports WHERE iataid = 
            (SELECT airports_iataid FROM ratelegs 
                WHERE shipments_shipid = c.shipments_shipid))
                ))) phone, 
depttime, arrivaltime, sum(linepcs), sum(lineweight)
FROM segment_times st
    JOIN contents2flights c2f 
        ON st.flightid = c2f.segments_flights_flightid 
        AND st.segmentid = c2f.segments_segmentid 
    JOIN contents c 
        ON c.lineno = c2f.contents_lineno 
        AND c.shipments_shipid = c2f.contents_shipments_shipid

WHERE c.shipments_shipid = var_shipid
GROUP BY flightid
ORDER BY flightdate, depttime;

Here is an example output:

airlinename         flt_no  flt_date        destination    phone         pcs   weight
Everts Air Alaska   CH1     2008-02-20      Hughes         9074502351    24    2121

The query inserts a bunch of flight data into a temporary table. I'm having trouble getting a phone number for a location. This part is as follows:

(SELECT phone 
FROM carrierlocations 
WHERE carriers_carrierid = (select carrierid from carriers where airlinename = st.airlinename) 
AND (city = destination OR (city != destination AND
    city = (SELECT city FROM airports WHERE iataid = 
            (SELECT airports_iataid FROM ratelegs 
                WHERE shipments_shipid = c.shipments_shipid))))) phone

, , , . , .

" : 1242. 1 "

+3
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. , .

SELECT column
FROM table
WHERE a = a1
AND (b = b1 OR (b != b1 AND (b = b2 OR (b != b2 AND b = b3))))
+1

IF() + IF() + IF(), sum = 1 , . 2 3 , 1. , 0. , .

SELECT column
  FROM table
  WHERE a = a1
    AND  if( b = b1, 1, 0 )
       + if( b = b2, 1, 0 )
       + if( b = b3, 1, 0 ) = 1

... ypercube, , 1, 0 true/false , ...

SELECT column
  FROM table
  WHERE a = a1
    AND  (b = b1) + (b = b2) + (b = b3) = 1
+3

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