BACKUP DATABASE

Info

MemSQL Helios does not support this command.

Backs up a database. The backup files are saved on the master aggregator and on the leaves.

Syntax

Backup to a Local or Network Drive

BACKUP [DATABASE] db_name TO "backup_path"

Backup to S3

BACKUP [DATABASE] db_name TO S3 "bucket/path" [CONFIG configuration_json] CREDENTIALS credentials_json

configuration_json:
'{"region":"your_region"},
  "suffixes":"list_of_file_extensions",
  "disable_gunzip":true|false
  "endpoint_url":"http://other_endpoint/"}'

credentials_json:
'{"aws_access_key_id": "replace_with_your_access_key_id",
  "aws_secret_access_key": "replace_with_your_secret_access_key",
  ["aws_session_token": "replace_with_your_temp_session_token",]
  ["role_arn":"replace_with_your_role_arn"]
}'

Optional S3 Configuration Values

  • region: AWS region where S3 bucket resides.
  • suffixes: Specifies the type of files that can be uploaded.
  • disable_gunzip: Determines whether decompressing archives (.gz files) happens automatically.
  • endpoint_url: Utilizes S3 backup to target S3-compatible storage targets.

Backup to Azure Blobs

BACKUP DATABASE db_name TO AZURE "container/blob-prefix" CREDENTIALS credentials_json

credentials_json:
'{"account_name": "your_account_name_here",
  "account_key": "your_account_key_here"
}'

Remarks

  • db_name is the name of a MemSQL database.
  • The BACKUP DATABASE command writes a consistent snapshot of the database to disk. This means a backup stores the data in the database as it existed at the time the BACKUP DATABASE operation started (all committed transactions at the time the BACKUP DATABASE started will be stored in the backup). Backup files containing the database’s reference tables are saved on the master aggregator. Backup files are also saved on the leaves.
    Info

    Backing up a database does not backup the users and grants for objects in the database. You must do this as a separate action. In addition, backing up a database does not back up engine variables, so the user must back up the memsql.cnf file and output of SHOW _SYNC VARIABLES LIKE '%' command from each node.

  • A backup of system databases cannot be created.
  • BACKUP DATABASE is an online operation, which means that writes will continue to run while the BACKUP DATABASE is in progress. Any writes executed after the BACKUP DATABASE has started will not be reflected in the stored backup.
  • All partitions of the database need to be in the online or replicating state to run a BACKUP DATABASE operation. The backup file is created on the server and not the client, unlike mysqldump.
  • This command must be run on the master aggregator node (see Node Requirements for MemSQL Commands).
  • The aggregator needs to briefly block new queries from running across the cluster to start a BACKUP DATABASE. Once the BACKUP DATABASE is running, queries can run against the cluster normally. If there is a long-running write query executing at the time a BACKUP DATABASE operation is run, the BACKUP DATABASE will wait for the query to finish.
  • MemSQL does not support BACKUP DATABASE on remote databases.

Back up to a Local or Network Drive

  • The backup_path is relative to the directory stored in the datadir engine variable, by default. You can include / at the front of the backup_path to override the default and use an absolute path.

Backup to S3

  • BACKUP ... TO S3 writes the backup files to the specified S3 bucket.
  • MemSQL backup will add db_name.backup to the path and put the objects in the path path/db_name.backup/.
  • bucket/path/db_name.backup must not currently exist; otherwise, an error will be returned.
  • aws_session_token is optional. This is only needed if your AWS account uses the AWS Security Token Service.
  • role_arn is optional and can be used instead of specifying aws_access_key_id and aws_secret_access_key values. This is only needed if your AWS security is setup to require a role.
  • Backup to a S3 bucket requires the following permissions:
  s3::GetObject
  s3::PutObject
  s3::ListBucket

Back up to Azure Blobs

  • BACKUP ... TO AZURE writes the backup files to the specified Azure container.
  • MemSQL backup will append db_name.backup to the blob prefix and and will put objects into the “path” blob-prefix/db_name.backup/.
  • container/blob-prefix/db_name.backup must not currently exist; otherwise, an error will be returned.

Examples

Local Backup

The following example backs up a database to /my-backup-dir.

BACKUP DATABASE memsql_demo to "/my-backup-dir";

The following example backs up a database to the directory stored in the datadir engine variable.

BACKUP DATABASE memsql_demo to "./";

The following example backs up a database to the my-relative-backup-dir directory, which is relative to the directory stored in the datadir engine variable. In this example, if datadir contained the directory /var/lib/memsql/leaf-3308-aaaaaaaaaa/data, the backup would be saved to the /var/lib/memsql/leaf-3308-aaaaaaaaaa/data/my-relative-backup-dir directory.

BACKUP DATABASE memsql_demo to "./my-relative-backup-dir";

S3 Backup

The following example backs up a database to an S3 bucket.

BACKUP DATABASE memsql_demo TO S3 "backup_bucket/backups/6_1_2018"
CONFIG '{"region":"us-east-1"}'
CREDENTIALS '{"aws_access_key_id":"your_access_key_id","aws_secret_access_key":"your_secret_access_key"}';

The following example backs up a database to an S3 bucket using an Amazon Resource Name (ARN) for AWS Identity and Access Management (IAM).

BACKUP DATABASE mydatabase TO S3 'my-bucket/memsql-backup/'
CONFIG '{"region": "us-east-1"}'
CREDENTIALS '{"role_arn": "arn:aws:iam::<AccountID>:role/EC2AmazonS3FullAccess"}';

Azure Blobs Backup

The following example backs up a database to an Azure bucket.

BACKUP DATABASE memsql_demo TO Azure "backup_container/backups/6_1_2018"
CREDENTIALS '{"account_name":"your_account_name_here","account_key":"your_account_key_here"}';

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