mysqlerror
附上错误日志：
2015-06-23 22:39:06 1252 [note] giving 0 client threads a chance to die gracefully
2015-06-23 22:39:06 1252 [note] shutting down slave threads
2015-06-23 22:39:06 1252 [note] forcefully disconnecting 0 remaining clients
2015-06-23 22:39:06 1252 [note] binlog end
2015-06-23 22:39:09 1252 [note] shutting down plugin 'partition'
2015-06-23 22:39:09 1252 [note] shutting down plugin 'blackhole'
2015-06-23 22:39:09 1252 [note] shutting down plugin 'performance_schema'
2015-06-23 22:39:09 1252 [note] shutting down plugin 'innodb_sys_datafiles'
2015-06-23 22:39:09 1252 [note] shutting down plugin 'innodb_sys_tablespaces'
2015-06-23 22:39:09 1252 [note] shutting down plugin 'innodb_sys_foreign_cols'
2015-06-23 22:39:09 1252 [note] shutting down plugin 'innodb_sys_foreign'
2015-06-23 22:39:09 1252 [note] shutting down plugin 'innodb_sys_fields'
2015-06-23 22:39:09 1252 [note] shutting down plugin 'innodb_sys_columns'
2015-06-23 22:39:09 1252 [note] shutting down plugin 'innodb_sys_indexes'
2015-06-23 22:39:09 1252 [note] shutting down plugin 'innodb_sys_tablestats'
2015-06-23 22:39:09 1252 [note] shutting down plugin 'innodb_sys_tables'
2015-06-23 22:39:09 1252 [note] shutting down plugin 'innodb_ft_index_table'
2015-06-23 22:39:09 1252 [note] shutting down plugin 'innodb_ft_index_cache'
2015-06-23 22:39:09 1252 [note] shutting down plugin 'innodb_ft_config'
2015-06-23 22:39:09 1252 [note] shutting down plugin 'innodb_ft_being_deleted'
2015-06-23 22:39:09 1252 [note] shutting down plugin 'innodb_ft_deleted'
2015-06-23 22:39:09 1252 [note] shutting down plugin 'innodb_ft_default_stopword'
2015-06-23 22:39:09 1252 [note] shutting down plugin 'innodb_metrics'
2015-06-23 22:39:09 1252 [note] shutting down plugin 'innodb_buffer_pool_stats'
2015-06-23 22:39:09 1252 [note] shutting down plugin 'innodb_buffer_page_lru'
2015-06-23 22:39:09 1252 [note] shutting down plugin 'innodb_buffer_page'
2015-06-23 22:39:09 1252 [note] shutting down plugin 'innodb_cmp_per_index_reset'
2015-06-23 22:39:09 1252 [note] shutting down plugin 'innodb_cmp_per_index'
2015-06-23 22:39:09 1252 [note] shutting down plugin 'innodb_cmpmem_reset'
2015-06-23 22:39:09 1252 [note] shutting down plugin 'innodb_cmpmem'
2015-06-23 22:39:09 1252 [note] shutting down plugin 'innodb_cmp_reset'
2015-06-23 22:39:09 1252 [note] shutting down plugin 'innodb_cmp'
2015-06-23 22:39:09 1252 [note] shutting down plugin 'innodb_lock_waits'
2015-06-23 22:39:09 1252 [note] shutting down plugin 'innodb_locks'
2015-06-23 22:39:09 1252 [note] shutting down plugin 'innodb_trx'
2015-06-23 22:39:09 1252 [note] shutting down plugin 'innodb'
2015-06-23 22:39:09 1252 [note] innodb: fts optimize thread exiting.
2015-06-23 22:39:09 1252 [note] innodb: starting shutdown...
2015-06-23 22:39:12 1252 [note] innodb: shutdown completed; log sequence number 44832642
2015-06-23 22:39:12 1252 [note] shutting down plugin 'archive'
2015-06-23 22:39:12 1252 [note] shutting down plugin 'myisam'
2015-06-23 22:39:12 1252 [note] shutting down plugin 'csv'
2015-06-23 22:39:12 1252 [note] shutting down plugin 'mrg_myisam'
2015-06-23 22:39:12 1252 [note] shutting down plugin 'memory'
2015-06-23 22:39:12 1252 [note] shutting down plugin 'sha256_password'
2015-06-23 22:39:12 1252 [note] shutting down plugin 'mysql_old_password'
2015-06-23 22:39:12 1252 [note] shutting down plugin 'mysql_native_password'
2015-06-23 22:39:12 1252 [note] shutting down plugin 'binlog'
2015-06-23 22:39:12 1252 [note] /usr/sbin/mysqld: shutdown complete
150623 22:39:12 mysqld_safe mysqld from pid file /var/run/mysqld/mysqld.pid ended
150623 22:39:39 mysqld_safe starting mysqld daemon with databases from /var/lib/mysql
2015-06-23 22:39:39 0 [warning] timestamp with implicit default value is deprecated. please use --explicit_defaults_for_timestamp server option (see documentation for more details).
2015-06-23 22:39:39 1190 [warning] buffered warning: changed limits: max_open_files: 1024 (requested 5000)
2015-06-23 22:39:39 1190 [warning] buffered warning: changed limits: table_cache: 431 (requested 2000)
2015-06-23 22:39:39 1190 [note] plugin 'federated' is disabled.
2015-06-23 22:39:39 1190 [note] innodb: using atomics to ref count buffer pool pages
2015-06-23 22:39:39 1190 [note] innodb: the innodb memory heap is disabled
2015-06-23 22:39:39 1190 [note] innodb: mutexes and rw_locks use gcc atomic builtins
2015-06-23 22:39:39 1190 [note] innodb: memory barrier is not used
2015-06-23 22:39:39 1190 [note] innodb: compressed tables use zlib 1.2.3
2015-06-23 22:39:39 1190 [note] innodb: using linux native aio
2015-06-23 22:39:39 1190 [note] innodb: not using cpu crc32 instructions
2015-06-23 22:39:39 1190 [note] innodb: initializing buffer pool, size = 1.0g
2015-06-23 22:39:40 1190 [note] innodb: completed initialization of buffer pool
2015-06-23 22:39:40 1190 [note] innodb: highest supported file format is barracuda.
2015-06-23 22:39:40 1190 [note] innodb: 128 rollback segment(s) are active.
2015-06-23 22:39:40 1190 [note] innodb: waiting for purge to start
2015-06-23 22:39:40 1190 [note] innodb: 5.6.22 started; log sequence number 44832642
2015-06-23 22:39:41 1190 [note] server hostname (bind-address): '*'; port: 3306
2015-06-23 22:39:41 1190 [note] ipv6 is available.
2015-06-23 22:39:41 1190 [note] - '::' resolves to '::';
2015-06-23 22:39:41 1190 [note] server socket created on ip: '::'.
2015-06-23 22:39:41 1190 [error] incorrect definition of table mysql.db: expected column 'user' at position 2 to have type char(16), found type char(80).
2015-06-23 22:39:41 1190 [error] incorrect definition of table mysql.event: expected column 'definer' at position 3 to have type char(77), found type char(141).
2015-06-23 22:39:41 1190 [error] incorrect definition of table mysql.event: expected column 'sql_mode' at position 14 to have type set('real_as_float','pipes_as_concat','ansi_quotes','ignore_space','not_used','only_full_group_by','no_unsigned_subtraction','no_dir_in_create','postgresql','oracle','mssql','db2','maxdb','no_key_options','no_table_options','no_field_options','mysql323','mysql40','ansi','no_auto_value_on_zero','no_backslash_escapes','strict_trans_tables','strict_all_tables','no_zero_in_date','no_zero_date','invalid_dates','error_for_division_by_zero','traditional','no_auto_create_user','high_not_precedence','no_engine_substitution','pad_char_to_full_length'), found type set('real_as_float','pipes_as_concat','ansi_quotes','ignore_space','ignore_bad_table_options','only_full_group_by','no_unsigned_subtraction','no_dir_in_create','postgresql','oracle','mssql','db2','maxdb','no_key_options','no_table_options','no_field_options','mysql323','mysql40','ansi','no_auto_value_on_zero','no_backslash_escapes','strict_trans_tables','strict_a
2015-06-23 22:39:41 1190 [error] event scheduler: an error occurred when initializing system tables. disabling the event scheduler.
2015-06-23 22:39:41 1190 [note] /usr/sbin/mysqld: ready for connections.
version: '5.6.22' socket: '/var/lib/mysql/mysql.sock' port: 3306 mysql community server (gpl)
2015-06-23 23:00:47 7f7038bc0700 innodb: error: column last_update in table mysql.innodb_table_stats is int unsigned not null but should be binary(4) not null (type mismatch).
2015-06-23 23:00:47 7f7038bc0700 innodb: error: fetch of persistent statistics requested for table moodle.mdl_config but the required system tables mysql.innodb_table_stats and mysql.innodb_index_stats are not present or have unexpected structure. using transient stats instead.