Mysql で Employee データベースを使用しています。私のデータベースには次のテーブルが含まれています
mysql> describe edept;
+-------+-------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------+-------------+------+-----+---------+-------+
| id | int(11) | NO | PRI | NULL | |
| dept | varchar(20) | NO | | NULL | |
+-------+-------------+------+-----+---------+-------+
mysql>describe esal;
+-------+---------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------+---------+------+-----+---------+-------+
| id | int(11) | NO | PRI | NULL | |
| basic | int(11) | NO | | NULL | |
| pf | int(11) | NO | | NULL | |
+-------+---------+------+-----+---------+-------+
mysql> describe edesig;
+-------+-------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------+-------------+------+-----+---------+-------+
| id | int(11) | NO | PRI | NULL | |
| desig | varchar(20) | NO | | NULL | |
+-------+-------------+------+-----+---------+-------+
mysql> select * from edetails inner join edept on edetails.dept=edept.id;
+----+--------+-----+------+-------+-------+----+----+------------------+
| id | name | age | dept | desig | basic | pf | id | dept |
+----+--------+-----+------+-------+-------+----+----+------------------+
| 1 | swetha | 21 | 3 | 2 | 2 | 2 | 3 | Business Process |
+----+--------+-----+------+-------+-------+----+----+------------------+
mysql> describe edetails;
+-------+-------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------+-------------+------+-----+---------+-------+
| id | int(11) | NO | PRI | NULL | |
| name | varchar(20) | NO | | NULL | |
| age | int(11) | NO | | NULL | |
| dept | int(11) | NO | MUL | NULL | |
| desig | int(11) | YES | MUL | NULL | |
| basic | int(11) | NO | MUL | NULL | |
| pf | int(11) | NO | MUL | NULL | |
+-------+-------------+------+-----+---------+-------+
テーブル edept.dept、edesig.desig、esal.basic、esal.pf からそれぞれ dept、desig、basic、pfの値を取得する必要があります。
他のテーブルから値を取得する必要があるすべてのフィールドに外部キーを使用しました。そして、サンプルの内部結合クエリを試しました。しかし、私は次のように出力を得ました：
mysql> select * from edetails inner join edept on edetails.dept=edept.id;
+----+--------+-----+------+-------+-------+----+----+------------------+
| id | name | age | dept | desig | basic | pf | id | dept |
+----+--------+-----+------+-------+-------+----+----+------------------+
| 1 | swetha | 21 | 3 | 2 | 2 | 2 | 3 | Business Process |
+----+--------+-----+------+-------+-------+----+----+------------------+
My edept table contains the following:
mysql> select * from edept;
+----+------------------+
| id | dept |
+----+------------------+
| 3 | Business Process |
+----+------------------+
How can i eliminate duplicate columns. i need the value "business process" in the dept field of the edept table