我有3张桌子：
table "f" (26000 record)
+------------------+------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+------------------+------------------+------+-----+---------+-------+
| idFascicolo | int(11) | NO | PRI | | |
| oggetto | varchar | NO |index| | |
+------------------+------------------+------+-----+---------+-------+
table "r" (22000 record)
+------------------+------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+------------------+------------------+------+-----+---------+-------+
| idRichiedente | int(11) | NO | PRI | | |
| name | varchar | NO |index| | |
+------------------+------------------+------+-----+---------+-------+
table "fr" (32000 record)
+------------------+------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+------------------+------------------+------+-----+---------+-------+
| id | int(11) | NO | PRI | | |
| idFascicolo | int(11) | NO |index| | FK |
| idRichiedente | int(11) | NO |index| | FK |
+------------------+------------------+------+-----+---------+-------+
这是我的选择：
SELECT
f.idFascicolo,
f.oggetto,
r.richiedente
FROM fr
JOIN f ON (f.idFascicolo=fr.idFascicolo)
JOIN r ON (r.idRichiedente=fr.idRichiedente)
WHERE r.name LIKE 'string%'
如何在不使用GROUP BY的情况下删除结果中的重复项（即“ Rossi Mario”和“ Rossi Marco”可以是f.idFascicolo的两个r.name）？
如何使用WHERE子句删除重复项？！
在this post中建议不要使用GROUP BY，但是我不知道该怎么做！ 非常感谢！
数据示例：
"r" data
+---------------+------------------------
| idRichiedente | name |
+---------------+-----------------------+
| 1 | Rossi Mario |
+---------------+-----------------------+
| 2 | Rossi Marco |
+---------------+-----------------------+
"f" data
+---------------+-----------------------+
| idFascicolo | oggetto |
+---------------+-----------------------+
| 1 | oggetto1 |
+---------------+-----------------------+
| 2 | oggetto2..o |
+---------------+-----------------------+
"fr" data
+---------------+-----------------------+-----------------+
| id | idFascicolo | idRichiedente |
+---------------+-----------------------+-----------------+
| 1 | 1 | 1 |
+---------------+-----------------------+-----------------+
| 2 | 1 | 2 |
+---------------+-----------------------+-----------------+