mySQL查询-简单的数学问题

Question

我每个人有两个电话号码。他们中的一些人只填写了电话，另一些人只填写了telephone2，还有的两个都填写了。

我正在尝试查找具有相同电话号码的其他人，无论是电话=电话、电话= telephone2、telephone2 =电话、telephone2 = telephone2

问题是，如果telephone1为null，那么我的现有代码将把它与具有电话号码的下一个人匹配，而不管它是否具有电话或telephone2 null。我需要向代码中添加什么。

    function getothers($tid,$criteria,$telephone,$telephone2,$elector){
                global $dbh;
                $tid = '-TID'.$tid;
                 $sql = "SELECT * FROM electors 
WHERE (telephone > 0 OR telephone2 > 0)
AND records NOT RLIKE '$tid'
AND (telephone IN ('$telephone','$telephone2') 
OR telephone2 IN ('$telephone','$telephone2')) 
AND ID != '$elector'  LIMIT 10";
                return $dbh->query($sql);
            }

Answer 1

SELECT T_el.*
FROM (electors AS T_el) LEFT JOIN (electors AS T_dup)
ON (T_el.ID!=T_dup.ID
  AND (
    (T_el.telephone IS NOT NULL AND (T_el.telephone=T_dup.telephone OR T_el.telephone=T_dup.telephone2))
    OR
    (T_el.telephone2 IS NOT NULL AND (T_el.telephone2=T_dup.telephone OR T_el.telephone2=T_dup.telephone2))
    )
)
WHERE T_dup.ID IS NOT NULL
GROUP BY T_el.ID

Answer 2

function getothers($tid,$criteria,$telephone,$telephone2,$elector){
            global $dbh;
            $tid = '-TID'.$tid;
             $sql = "SELECT * FROM electors WHERE (telephone > 0 AND telephone IN ('$telephone','$telephone2'))  OR (telephone2 > 0 AND telephone2 IN ('$telephone','$telephone2')) $criteria AND records NOT RLIKE '$tid' AND ID != '$elector'  LIMIT 10";
            return $dbh->query($sql);
        }