Removing Duplicates of a Particular Row

        
mysql>
mysql> CREATE TABLE t
    -> (
    ->  color CHAR(10)
    -> )
    -> ;
Query OK, 0 rows affected (0.01 sec)

mysql>
mysql> INSERT INTO t(color)
    -> VALUES('blue'),('green'),('indigo'),('orange'),('red'),('violet'),('yellow')
    -> ;
Query OK, 7 rows affected (0.00 sec)
Records: 7  Duplicates: 0  Warnings: 0

mysql>
mysql> SELECT name FROM color;
+--------+
| name   |
+--------+
| blue   |
| green  |
| indigo |
| orange |
| red    |
| violet |
| yellow |
+--------+
7 rows in set (0.00 sec)

mysql>
mysql>
mysql> DELETE FROM t WHERE color = 'blue' LIMIT 2;
Query OK, 1 row affected (0.00 sec)

mysql> DELETE FROM t WHERE color = 'green' LIMIT 1;
Query OK, 1 row affected (0.00 sec)

mysql> DELETE FROM t WHERE color = 'red' LIMIT 1;
Query OK, 1 row affected (0.00 sec)

mysql> SELECT * FROM t;
+--------+
| color  |
+--------+
| indigo |
| orange |
| violet |
| yellow |
+--------+
4 rows in set (0.00 sec)

mysql>
mysql> drop table t;
Query OK, 0 rows affected (0.00 sec)

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Removing Duplicates of a Particular Row : COUNT « Aggregate Functions « SQL / MySQL

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