Over a million developers have joined DZone.

How to Export and Import MySQL Databases

DZone's Guide to

How to Export and Import MySQL Databases

· Java Zone
Free Resource

Learn how to troubleshoot and diagnose some of the most common performance issues in Java today. Brought to you in partnership with AppDynamics.

You can export the MySQL database with schema table definitions and data separated. Here is a simple bash shell script that will export an database.

# file: database-export.sh

# export schema only from mysql 
echo "`date` Exporting database $DB_NAME schema to $DB_SCHEMA_FILE"
mysqldump --no-data --routines -u $DB_USERNAME -p$DB_PASSWORD $DB_NAME > $DB_SCHEMA_FILE

# export data only from mysql
echo "`date` Exporting database $DB_NAME data to $DB_DATA_FILE"
mysqldump --single-transaction --quick --no-autocommit --no-create-info --extended-insert=false -u $DB_USERNAME -p$DB_PASSWORD $DB_NAME > $DB_DATA_FILE

echo "`date` Done."

The schema export with "--routines" will export stored proc as well. When exporitng data you have to be little more careful. The "--single-transaction" will ensure your data is good. The "--no-autocommit" can really speed up your import later on certain OS.

Now to import these files back, you can create an empty database and then run the following.

# file: database-import.sh
# import schema and data into mysql
echo "`date` Importing Schema $DB_SCHEMA_FILE into $DB_NAME"
echo "`date` Importing DATA $DB_DATA_FILE into $DB_NAME"

echo "`date` Done."

The import with "-f" option will allow you to continue even if you already have duplicated data in the tables; it will simply ignore and continue.

These two combo commands will allow you to quicly backup and restore a MySQL database.


PS: I have come to learn that "mysqldump" with procedures will insert an extra line like "DEFINER 'user'@'hostname'", and it may create problem if you use different users to export/import or even run the application! Unfortunately there is no exclude from the "mysqldump" tool. So you have to manually strip that off if that's creating a problem for you.

mysqldump --no-data --routines -u $DB_USERNAME -p$DB_PASSWORD $DB_NAME | perl -pi -e 's/DEFINER="\w+"@"\w+" //g' > $DB_SCHEMA_FILE

You can vote the issue here: http://bugs.mysql.com/bug.php?id=24680

Understand the needs and benefits around implementing the right monitoring solution for a growing containerized market. Brought to you in partnership with AppDynamics.


Published at DZone with permission of Zemian Deng, DZone MVB. See the original article here.

Opinions expressed by DZone contributors are their own.

{{ parent.title || parent.header.title}}

{{ parent.tldr }}

{{ parent.urlSource.name }}