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$dupesql = "SELECT * FROM table where (name = '$name' AND description = '$description' AND manufacturer = '$manufacturer' AND city ='$city' AND price = '$price' AND enddate = '$end_date')";
$duperaw = mysql_query($dupesql);
if (mysql_num_rows($duperaw) > 0) {
//your code ...
}
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SELECT t1.name, t1.street, t1.house, GROUP_CONCAT(DISTINCT t1.id) dupes
FROM your_table t1
JOIN your_table t2 ON (t2.name = t1.name AND
t2.street = t1.street AND
t2.house = t1.house)
GROUP BY t1.name, t1.street, t1.house
HAVING COUNT(*) > 1;