MySQL Dump configuration file

Question

I modified th my.cnf file, so that the innodb_data_file_path points somewhere else from the default path. But the mysqldump command seems like trying to dump from the default path.

I found that if i give the option --defaults-file=xxxx in command line i could change it, but is there a way to config mysqldump to use this option without specify it in command line?

Answer 1

Unfortunately, there is no mechanism for innodb_data_file_path in terms of a mysqldump.

You could set mysqldump options in /etc/my.cnf. Simply go to the bottom and add the following

[mysqldump]
routines
triggers
force

Then, whenever you launch mysqldump, these options are read.

Contrariwise, innodb_data_file_path is a storage-engine specific option for mysqld. You cannot place innodb_data_file_path under a [mysqldump] group header. When calling mysqldump, whatever the MySQL Instance has set, that's what mysqldump uses.

Please put back the original innodb_data_file_path or MySQL will fail to start upon the next restart of mysqld.

You need to check out if InnoDB is functional. Please run SHOW ENGINES;. You should see:

mysql> SHOW ENGINES;
+--------------------+---------+----------------------------------------------------------------+--------------+------+------------+
| Engine             | Support | Comment                                                        | Transactions | XA   | Savepoints |
+--------------------+---------+----------------------------------------------------------------+--------------+------+------------+
| FEDERATED          | YES     | Federated MySQL storage engine                                 | NO           | NO   | NO         |
| MRG_MYISAM         | YES     | Collection of identical MyISAM tables                          | NO           | NO   | NO         |
| MyISAM             | YES     | MyISAM storage engine                                          | NO           | NO   | NO         |
| BLACKHOLE          | YES     | /dev/null storage engine (anything you write to it disappears) | NO           | NO   | NO         |
| CSV                | YES     | CSV storage engine                                             | NO           | NO   | NO         |
| MEMORY             | YES     | Hash based, stored in memory, useful for temporary tables      | NO           | NO   | NO         |
| ARCHIVE            | YES     | Archive storage engine                                         | NO           | NO   | NO         |
| InnoDB             | DEFAULT | Supports transactions, row-level locking, and foreign keys     | YES          | YES  | YES        |
| PERFORMANCE_SCHEMA | YES     | Performance Schema                                             | NO           | NO   | NO         |
+--------------------+---------+----------------------------------------------------------------+--------------+------+------------+
9 rows in set (0.03 sec)

mysql> 

If InnoDB does not appear, check the my.cnf for typos. In fact, you have comment that says

innodb_data_file_path =Qibdata1:10M:autoextend

This could cause a disconnect between ibdata1 (which houses the data dictionary and other things) and the datadir for each database that has one or more .frm files for InnoDB tables.