用group by和 HAVING count(part_no)去重
下面这个语句是只显示重复行中的一行
mysql> SELECT part_no FROM e787_software_part GROUP BY part_no HAVING count(part_no)>1 limit 3;
+-----------------+
| part_no |
+-----------------+
| BCG23-U000-0264 |
| BCG27-0000-00X9 |
| BCG29-0000-00X7 |
+-----------------+
3 rows in set (0.00 sec)
mysql> select part_no FROM e787_software_part where part_no='BCG23-U000-0264';
+-----------------+
| part_no |
+-----------------+
| BCG23-U000-0264 |
| BCG23-U000-0264 |
+-----------------+
2 rows in set (0.00 sec)
mysql> select part_no FROM e787_software_part where part_no='BCG27-0000-00X9';
+-----------------+
| part_no |
+-----------------+
| BCG27-0000-00X9 |
| BCG27-0000-00X9 |
+-----------------+
2 rows in set (0.00 sec)