mysqldump problems with restore error: 'Please DISCARD the tablespace before IMPORT'

问题

I run a daily backup mysqldump backup of the production database (mysql version 5.1.66):

mysqldump --user=username --password=secret -C -e --create-options --hex-blob --net_buffer_length=5000 databasename > file

I also do a daily restore of that database on my development machine (mysql version 5.6.12)

mysql --user=username --password=secret databasename < file

I get the error: ERROR 1813 (HY000) at line 25: Tablespace for table 'databasename.tablename' exists. Please DISCARD the tablespace before IMPORT.

My reading indicates this is because the mysql innodb database requires the command:

 ALTER TABLE tbl_name DISCARD TABLESPACE;

to be run before the table is dropped -- it seems that dropping the table isn't sufficient to get rid of its indexes. (my development server uses the innodb_file_per_table option)

I don't want to use 'replace' option because i could potentially have data in my development database that was deleted on the production database.

btw after the error the tables are not readable, but restarting mysqld fixes it.

So the question is, is there any mysql dump option that will help fix this issue, or is there another way to import the data that will prevent the error?

thanks in advance for reading.

回答1:

Sounds like you have a tablename.ibd but no tablename.frm.

To check:

cd to your mysql data directory then the database name.
```
cd /var/lib/mysql/database_name
```
Search for the table name that is giving the error.
```
ls tablename.*
```
You should see two files:
```
tablename.ibd
tablename.frm
```
But I'm guessing you don't and only see
```
tablename.ibd
```

To fix you have a few options:

Add the follow to mysqldump, which will cause the database to be dropped, cleaning up data directory, before restore.
```
--add-drop-database
```
Copy the tablename.frm from prod over to dev and then issue a delete table statement.

Also:

No need to use net_buffer_length=5000 when you're dumping to a file on localhost.
Other backup solutions - Percona Xtrabackup

回答2:

I found the easiest way to skip this problem was to manually edit phpmyadmin database dump and edit/change the table that had problems to something else than INNODB. I changed the problem table to ENGINE=MyISAM and voila. Import worked.

CREATE TABLE IF NOT EXISTS `home3_acymailing_tag` (
    `tagid` smallint(5) unsigned NOT NULL AUTO_INCREMENT,
    `name` varchar(250) NOT NULL,
    `userid` int(10) unsigned DEFAULT NULL,
    PRIMARY KEY (`tagid`),
    KEY `useridindex` (`userid`)
) ENGINE=MyISAM DEFAULT CHARSET=utf8 AUTO_INCREMENT=1 ;

回答3:

I also encountered that problem while dropping a schema and creating it again. I overcome this issue by going C:\ProgramData\MySQL\MySQL Server 5.6\data\my_database_name and deleting the tables which remained from the previous database creation. You can also delete the entire database, if you wish.

回答4:

if you are using XAMPP then first ("stop") MySQL Then go to C:\xampp\mysql\data\dnb where in my case dnb is my database name folder. so then open it and delete .ibd file hence you can only delete it when you already stop MYsql . then go to phpmyadmin 1 click on phpmyadmin . 2 click on databases that appear below (server.127.0.0.1 in your case my be change) 3 then check your database which you want to drop,and click on drop. 4 then you can create database with same name and import your database successfully .here you can see how you drop database from phpmyadmin

来源：https://stackoverflow.com/questions/17914446/mysqldump-problems-with-restore-error-please-discard-the-tablespace-before-imp

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mysql

mysqldump