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MySQL

Overview

The MySQL source supports both Full Refresh and Incremental syncs. You can choose if this connector will copy only the new or updated data, or all rows in the tables and columns you set up for replication, every time a sync is run.

Resulting schema

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.

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
array array
bigint number
binary string
blob string
date string
datetime string
decimal number
decimal(19, 2) number
double number
enum string
float number
int number
int unsigned number
int zerofill number
json text
mediumint number
mediumint zerofill number
mediumint number
numeric number
point object
smallint number
smallint zerofill number
string string
tinyint number
text string
time string
timestamp string
tinytext string
varbinary(256) string
varchar string
varchar(256) character set cp1251 string
varchar(256) character set utf16 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.

Note: arrays for all the above types as well as custom types are supported, although they may be de-nested depending on the destination. Byte arrays are currently unsupported.

Features

Feature Supported Notes
Full Refresh Sync Yes
Incremental - Append Sync Yes
Replicate Incremental Deletes Yes
CDC Yes
SSL Support Yes
SSH Tunnel Connection Coming soon
Namespaces Yes Enabled by default

Getting started

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

Setup guide

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.

Setting up CDC for MySQL

You must enable binary logging for MySQL replication. The binary logs record transaction updates for replication tools to propagate changes.

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.

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.

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.

Changelog

Version Date Pull Request Subject
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