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Several solutions for a few mysql errors


1062 Duplicate entry 'xxxx' for key xxxx.
The key is already in current mysql. In mysql slave server, try "STOP SLAVE;SET GLOBAL SQL_SLAVE_SKIP_COUNTER = 1;START SLAVE;". You may also set slave_skip_errors = 1062 in my.cnf file to ignore all the 1062 errors.

1236  Got fatal error 1236 from master when reading data from binary log: 'Client requested master to start replication from impossible position'
The binlog position in master mysql server is not available. Some problem of master mysql server may cause this issue. You may want change the mysql replication position to next binary log file on the master mysql server(using "change master to ...").

126 Error 'Incorrect key file for table './db/xxx.MYI'; try to repair it' on query.
The error means that index file is crashed, and you may repair it by "repair table xxx". Or you want to change mysql storage to another hard disk since the error my be induced by an disk error.

I also found another solution in http://techpolesen.blogspot.com/2007/06/problems-with-file-upload-into-mysql-in.html . The space in /tmp is too small for mysql to store big intermediate results, so you may change(add) tmpdir settings in my.cnf to another location to solve the problem. However, you may encounter "Errcode 13" if you specify a location like /home/ubuntu/tmp for tmpdir. Make sure you give it 1777 permission(chmod 1777 /home/ubuntu/tmp) and enable r/w of the directory in /etc/apparmer.d/usr.sbin.mysqld by add "/home/ubuntu/tmp/** rw," with in {} of /usr/ubuntu/tmp.

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