Let’s say you have set column values as unique key and try to insert duplicate values in the table. This will lead to ERROR 1062 (23000): Duplicate entry.
Let us first create a table -
mysql> create table DemoTable776 ( FirstValue int, SecondValue int, unique key(FirstValue,SecondValue) ); Query OK, 0 rows affected (0.74 sec)
Insert some records in the table using insert command. While inserting duplicate value, the same error arises as shown below -
mysql> insert into DemoTable776 values(10,20); Query OK, 1 row affected (0.16 sec) mysql> insert into DemoTable776 values(10,40); Query OK, 1 row affected (0.15 sec) mysql> insert into DemoTable776 values(40,20); Query OK, 1 row affected (0.26 sec) mysql> insert into DemoTable776 values(10,20); ERROR 1062 (23000): Duplicate entry '10-20' for key 'FirstValue'
Display all records from the table using select statement -
mysql> select *from DemoTable776;
This will produce the following output -
+------------+-------------+ | FirstValue | SecondValue | +------------+-------------+ | 10 | 20 | | 10 | 40 | | 40 | 20 | +------------+-------------+ 3 rows in set (0.00 sec)