MySQL error 1062 - Duplicate entry when starting slave or replication fail?

Duplicate entry when starting slave? MySQL error 1062

Why does replication fail with error Duplicate entry for key?

following error when executing the mysql> start slave;:

    Last_SQL_Errno: 1062

    Last_SQL_Error: Error 'Duplicate entry '115846' for key

'PRIMARY'' on query. Default database: 'db'. Query: 'INSERT INTO

request_posted (id, user_id, channel, message, link, picture, name, ...

Solution :-

Try to skip some queries with:

mysql> STOP SLAVE; 
mysql> SET GLOBAL SQL_SLAVE_SKIP_COUNTER=1; 
mysql> START SLAVE;