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MySQL

Features

Feature Supported Notes
Full Refresh Sync Yes
Incremental - Append Sync Yes
Replicate Incremental Deletes Yes
CDC Yes
SSL Support Yes
SSH Tunnel Connection Yes
Namespaces Yes Enabled by default
Arrays Yes Byte arrays are not supported yet

The MySQL source does not alter the schema present in your database. Depending on the destination connected to this source, however, the schema may be altered. See the destination's documentation for more details.

Troubleshooting

There may be problems with mapping values in MySQL's datetime field to other relational data stores. MySQL permits zero values for date/time instead of NULL which may not be accepted by other data stores. To work around this problem, you can pass the following key value pair in the JDBC connector of the source setting zerodatetimebehavior=Converttonull.

Getting Started (Airbyte Cloud)

On Airbyte Cloud, only TLS connections to your MySQL instance are supported. Other than that, you can proceed with the open-source instructions below.

Getting Started (Airbyte Open-Source)

Requirements

  1. MySQL Server 8.0, 5.7, or 5.6.
  2. Create a dedicated read-only Airbyte user with access to all tables needed for replication.

1. Make sure your database is accessible from the machine running Airbyte

This is dependent on your networking setup. The easiest way to verify if Airbyte is able to connect to your MySQL instance is via the check connection tool in the UI.

2. Create a dedicated read-only user with access to the relevant tables (Recommended but optional)

This step is optional but highly recommended to allow for better permission control and auditing. Alternatively, you can use Airbyte with an existing user in your database.

To create a dedicated database user, run the following commands against your database:

CREATE USER 'airbyte'@'%' IDENTIFIED BY 'your_password_here';

The right set of permissions differ between the STANDARD and CDC replication method. For STANDARD replication method, only SELECT permission is required.

GRANT SELECT ON <database name>.* TO 'airbyte'@'%';

For CDC replication method, SELECT, RELOAD, SHOW DATABASES, REPLICATION SLAVE, REPLICATION CLIENT permissions are required.

GRANT SELECT, RELOAD, SHOW DATABASES, REPLICATION SLAVE, REPLICATION CLIENT ON *.* TO 'airbyte'@'%';

Your database user should now be ready for use with Airbyte.

3. Set up CDC

For STANDARD replication method this is not applicable. If you select the CDC replication method then only this is required. Please read the section on CDC below for more information.

4. That's it!

Your database user should now be ready for use with Airbyte.

Change Data Capture (CDC)

  • If you need a record of deletions and can accept the limitations posted below, you should be able to use CDC for MySQL.
  • If your data set is small, and you just want snapshot of your table in the destination, consider using Full Refresh replication for your table instead of CDC.
  • If the limitations prevent you from using CDC and your goal is to maintain a snapshot of your table in the destination, consider using non-CDC incremental and occasionally reset the data and re-sync.
  • If your table has a primary key but doesn't have a reasonable cursor field for incremental syncing (i.e. updated_at), CDC allows you to sync your table incrementally.

CDC Limitations

  • Make sure to read our CDC docs to see limitations that impact all databases using CDC replication.
  • Our CDC implementation uses at least once delivery for all change records.

1. Enable binary logging

You must enable binary logging for MySQL replication. The binary logs record transaction updates for replication tools to propagate changes. You can configure your MySQL server configuration file with the following properties, which are described in below:

server-id         = 223344
log_bin           = mysql-bin
binlog_format     = ROW
binlog_row_image  = FULL
expire_logs_days  = 10
  • server-id : The value for the server-id must be unique for each server and replication client in the MySQL cluster. The server-id should be a non-zero value. If the server-id is already set to a non-zero value, you don't need to make any change. You can set the server-id to any value between 1 and 4294967295. For more information refer mysql doc
  • log_bin : The value of log_bin is the base name of the sequence of binlog files. If the log_bin is already set, you don't need to make any change. For more information refer mysql doc
  • binlog_format : The binlog_format must be set to ROW. For more information refer mysql doc
  • binlog_row_image : The binlog_row_image must be set to FULL. It determines how row images are written to the binary log. For more information refer mysql doc
  • expire_logs_days : This is the number of days for automatic binlog file removal. We recommend 10 days so that in case of a failure in sync or if the sync is paused, we still have some bandwidth to start from the last point in incremental sync. We also recommend setting frequent syncs for CDC.

2. Enable GTIDs (Optional)

Global transaction identifiers (GTIDs) uniquely identify transactions that occur on a server within a cluster. Though not required for a Airbyte MySQL connector, using GTIDs simplifies replication and enables you to more easily confirm if primary and replica servers are consistent. For more information refer mysql doc

  • Enable gtid_mode : Boolean that specifies whether GTID mode of the MySQL server is enabled or not. Enable it via mysql> gtid_mode=ON
  • Enable enforce_gtid_consistency : Boolean that specifies whether the server enforces GTID consistency by allowing the execution of statements that can be logged in a transactionally safe manner. Required when using GTIDs. Enable it via mysql> enforce_gtid_consistency=ON

Note

When a sync runs for the first time using CDC, Airbyte performs an initial consistent snapshot of your database. Airbyte doesn't acquire any table locks (for tables defined with MyISAM engine, the tables would still be locked) while creating the snapshot to allow writes by other database clients. But in order for the sync to work without any error/unexpected behaviour, it is assumed that no schema changes are happening while the snapshot is running.

Connection via SSH Tunnel

Airbyte has the ability to connect to a MySQl instance via an SSH Tunnel. The reason you might want to do this because it is not possible (or against security policy) to connect to the database directly (e.g. it does not have a public IP address).

When using an SSH tunnel, you are configuring Airbyte to connect to an intermediate server (a.k.a. a bastion sever) that does have direct access to the database. Airbyte connects to the bastion and then asks the bastion to connect directly to the server.

Using this feature requires additional configuration, when creating the source. We will talk through what each piece of configuration means.

  1. Configure all fields for the source as you normally would, except SSH Tunnel Method.
  2. SSH Tunnel Method defaults to No Tunnel (meaning a direct connection). If you want to use an SSH Tunnel choose SSH Key Authentication or Password Authentication.
    1. Choose Key Authentication if you will be using an RSA private key as your secret for establishing the SSH Tunnel (see below for more information on generating this key).
    2. Choose Password Authentication if you will be using a password as your secret for establishing the SSH Tunnel.
  3. SSH Tunnel Jump Server Host refers to the intermediate (bastion) server that Airbyte will connect to. This should be a hostname or an IP Address.
  4. SSH Connection Port is the port on the bastion server with which to make the SSH connection. The default port for SSH connections is 22, so unless you have explicitly changed something, go with the default.
  5. SSH Login Username is the username that Airbyte should use when connection to the bastion server. This is NOT the MySQl username.
  6. If you are using Password Authentication, then SSH Login Username should be set to the password of the User from the previous step. If you are using SSH Key Authentication leave this blank. Again, this is not the MySQl password, but the password for the OS-user that Airbyte is using to perform commands on the bastion.
  7. If you are using SSH Key Authentication, then SSH Private Key should be set to the RSA Private Key that you are using to create the SSH connection. This should be the full contents of the key file starting with -----BEGIN RSA PRIVATE KEY----- and ending with -----END RSA PRIVATE KEY-----.

Generating an SSH Key Pair

The connector expects an RSA key in PEM format. To generate this key:

ssh-keygen -t rsa -m PEM -f myuser_rsa

This produces the private key in pem format, and the public key remains in the standard format used by the authorized_keys file on your bastion host. The public key should be added to your bastion host to whichever user you want to use with Airbyte. The private key is provided via copy-and-paste to the Airbyte connector configuration screen, so it may log in to the bastion.

Data Type Mapping

MySQL data types are mapped to the following data types when synchronizing data. You can check the test values examples here. If you can't find the data type you are looking for or have any problems feel free to add a new test!

MySQL Type Resulting Type Notes
bit(1) boolean
bit(>1) base64 binary string
boolean boolean
tinyint(1) boolean
tinyint number
smallint number
mediumint number
int number
bigint number
float number
double number
decimal number
binary string
blob string
date string ISO 8601 date string. ZERO-DATE value will be converted to NULL.
datetime, timestamp string ISO 8601 datetime string. ZERO-DATE value will be converted to NULL.
time string ISO 8601 time string. Values are in range between 00:00:00 and 23:59:59.
year year string Doc
char, varchar with non-binary charset string
char, varchar with binary charset base64 binary string
tinyblob base64 binary string
blob base64 binary string
mediumblob base64 binary string
longblob base64 binary string
binary base64 binary string
varbinary base64 binary string
tinytext string
text string
mediumtext string
longtext string
json serialized json string E.g. {"a": 10, "b": 15}
enum string
set string E.g. blue,green,yellow
geometry base64 binary string

If you do not see a type in this list, assume that it is coerced into a string. We are happy to take feedback on preferred mappings.

Changelog

Version Date Pull Request Subject
0.5.0 2021-12-11 7970 Support all MySQL types
0.4.13 2021-12-03 8335 Source-MySql: do not check cdc required param binlog_row_image for standard replication
0.4.12 2021-12-01 8371 Fixed incorrect handling "\n" in ssh key
0.4.11 2021-11-19 8047 Source MySQL: transform binary data base64 format
0.4.10 2021-11-15 7820 Added basic performance test
0.4.9 2021-11-02 7559 Correctly process large unsigned short integer values which may fall outside java's Short data type capability
0.4.8 2021-09-16 6093 Improve reliability of processing various data types like decimals, dates, datetime, binary, and text
0.4.7 2021-09-30 6585 Improved SSH Tunnel key generation steps
0.4.6 2021-09-29 6510 Support SSL connection
0.4.5 2021-09-17 6146 Added option to connect to DB via SSH
0.4.1 2021-07-23 4956 Fix log link
0.3.7 2021-06-09 3179 Add AIRBYTE_ENTRYPOINT for Kubernetes support
0.3.6 2021-06-09 3966 Fix excessive logging for CDC method
0.3.5 2021-06-07 3890 Fix CDC handle tinyint(1) and boolean types
0.3.4 2021-06-04 3846 Fix max integer value failure
0.3.3 2021-06-02 3789 MySQL CDC poll wait 5 minutes when not received a single record
0.3.2 2021-06-01 3757 MySQL CDC poll 5s to 5 min
0.3.1 2021-06-01 3505 Implemented MySQL CDC
0.3.0 2021-04-21 2990 Support namespaces
0.2.5 2021-04-15 2899 Fix bug in tests
0.2.4 2021-03-28 2600 Add NCHAR and NVCHAR support to DB and cursor type casting
0.2.3 2021-03-26 2611 Add an optional jdbc_url_params in parameters
0.2.2 2021-03-26 2460 Destination supports destination sync mode
0.2.1 2021-03-18 2488 Sources support primary keys
0.2.0 2021-03-09 2238 Protocol allows future/unknown properties
0.1.10 2021-02-02 1887 Migrate AbstractJdbcSource to use iterators
0.1.9 2021-01-25 1746 Fix NPE in State Decorator
0.1.8 2021-01-19 1724 Fix JdbcSource handling of tables with same names in different schemas
0.1.7 2021-01-14 1655 Fix JdbcSource OOM
0.1.6 2021-01-08 1307 Migrate Postgres and MySQL to use new JdbcSource
0.1.5 2020-12-11 1267 Support incremental sync
0.1.4 2020-11-30 1046 Add connectors using an index YAML file