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Posted By

Abe on 01/29/08


Tagged

mysql database duplicate rows


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naz


Remove Duplicate Rows

Published in: PHP 

$duplicates checks and groups duplicated rows with the same field1 and field2 (like comments maybe) and $limit counts how many times a row is duplicated.

Plain TextExpand 
  1. <?php
  2. $duplicates = mysql_query("SELECT field1, field2, count(*) FROM table GROUP BY field1, field2 having count(*) > 1");
  3. $count = mysql_num_rows($duplicates);
  4. if ($count > 0) {
  5. 	while ($row = mysql_fetch_assoc($duplicates)) {
  6. 		$field = $row["field1"];
  7. 		$limit = $row["count(*)"] - 1;
  8. 		mysql_query("DELETE FROM table WHERE field1='$field' LIMIT $limit");
  9. 	}
  10. 	mysql_free_result($duplicates);
  11. }
  12. ?>

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