MySQL snapshot

Release status Released Supported by Stitch
Availability Free Supported Versions n/a
SSL connections Supported VPN Connections Unsupported
Data selection Tables and columns View Replication Supported
Destination
incompatibilities
None

Connecting MySQL

MySQL Setup Requirements

To set up MySQL in Stitch, you need:

  • The CREATE USER or INSERT privilege (for the mysql database). The CREATE USER privilege is required to create a database user for Stitch.

  • The GRANT OPTION privilege in MySQL. The GRANT OPTION privilege is required to grant the necessary privileges to the Stitch database user.

  • The SUPER privilege in MySQL. If using binlog replication, the SUPER privilege is required to define the appropriate server settings.


Step 1: Configure database connection settings

Choose your connection type

If your database is publicly accessible, you can directly connect it to Stitch.

If your database is not publicly accessible, you'll need to connect Stitch via an SSH tunnel.

Click the tab with your connection type to view the configuration instructions.

For the connection to be successful, you’ll need to configure your firewall to allow access from our IP addresses. Whitelist the following IPs before continuing onto the next step:

  • 52.23.137.21/32

  • 52.204.223.208/32

  • 52.204.228.32/32

  • 52.204.230.227/32

Step 1.1: Whitelist Stitch's IP addresses

For the connection to be successful, you’ll need to configure your firewall to allow access from our IP addresses. Whitelist the following IPs before continuing onto the next step:

  • 52.23.137.21/32

  • 52.204.223.208/32

  • 52.204.228.32/32

  • 52.204.230.227/32

Step 1.2: Retrieve your Stitch public key

The Stitch Public Key

The Public Key is used to authorize the Stitch Linux user. If the key isn’t properly installed, Stitch will be unable to access your database.

To retrieve the key:

  1. Sign into your Stitch account.

  2. On the Stitch Dashboard page, click the Add Integration button.

  3. Click the MySQL icon.

  4. Click the SSH Tunnel checkbox.

  5. The Public Key will display, along with the other SSH fields.

Leave this page open for now - you’ll need it to wrap things up at the end.

Step 1.3: Create a Stitch SSH user

Note: Anything inside square brackets - [like this] - is something you need to define when running the commands yourself.

  1. To create the new user, run the following commands as root on your Linux server:

    adduser --disabled-password [stitch_username]
    mkdir /home/[stitch_username]/.ssh
    
  2. Next, import the Public Key into authorized_keys. This will ensure the Stitch user has access to the database.

    Copy the entire key into the authorized_keys file by:

    "[PASTE KEY HERE]" >> /home/[stitch_username]/.ssh/authorized_keys
    
  3. Alter the permissions on the /home/[stitch_username] directory to allow access via SSH:

    chown -R [stitch_username]:[stitch_username] /home/[stitch_username]
    chmod -R 700 /home/[stitch_username]/.ssh
    

Step 2: Configure database server settings

Next, you’ll configure your server to use Log-based Incremental Replication, or binlog replication.

Log-based Incremental Replication is a method of replication that reads a database’s binary log files. These files contain information about modifications made to data in a MySQL instance. Log-based Incremental Replication captures all inserts, updates, and deletes made to records during each replication job, and is the most accurate and efficient method of replication.

While Stitch recommends using Log-based Replication to replicate data, it isn’t mandatory. Stitch offers additional Replication Methods for MySQL databases that don’t require defining these settings.

  1. Log into your MySQL server.
  2. Verify that binlog is enabled by running the following statement. The value returned should be 1:

    mysql> select @@log_bin;
    

    If this statement returns a 0, this means that binlog is disabled. You’ll enable it in the next step.

  3. Locate the my.cnf file, usually located at /etc/my.cnf. Verify that my.cnf has the following lines in the mysqld section:

    [mysqld]
    binlog_format=ROW
    binlog_row_image=FULL
    expire_logs_days=7
    binlog_expire_logs_seconds=604800
    log_bin=mysql-binlog
    log_slave_updates=1
    

    A few things to note:

    • log_bin doesn’t have to be mysql-binlog - this value can be anything. Additionally, if log_bin already has an entry (which you checked in step one), you don’t need to change it.
    • Use either expire_log_days or binlog_expire_logs_seconds, not both. See the Server settings list tab for more information.
    • Setting log_slave_updates is only required if you are connecting a read replica. This isn’t required for master instances.
  4. When finished, restart your MySQL server to ensure the changes take effect.

In the table below are the names, required values, and descriptions of the server settings you must define.

Setting Value Description
binlog_format ROW

Note: This setting is available on MySQL databases running version 5.6.2 or greater.

Defines the binary logging format. A ROW value enables “event-based” capture, which describes what happens to records in the database. This is necessary to use binlog.

Stitch supports the following event types:

  • INSERT
  • UPDATE
  • DELETE
binlog_row_image FULL

Note: This setting is available on MySQL databases running version 5.6.2 or greater.

Defines how row images are written to the binary log. A FULL value ensures that all columns in a row are logged in the before and after images of a change, enabling Stitch to accurately capture all changes made to a record.

expire_logs_days 7

Specifies the amount of time, in days, before the automatic removal of binary log files. Stitch recommends a retention period of 7 days, but a minimum of 3 days will also work.

Do not use both expire_logs_days and binlog_expire_logs_seconds - only define one. The value of this variable will be ignored if binlog_expire_logs_seconds also contains a value.

Note: This variable is deprecated as of MySQL version 8.0.3, and will be removed in a future release. If using MySQL versions 8.0.1+, use binlog_expire_logs_seconds instead.

binlog_expire_logs_seconds 604800

Specifies the amount of time, in seconds, before the automatic removal of binary log files. Stitch recommends a retention period of 7 days, but a minimum of 3 days will also work.

Note: This variable is available on MySQL versions 8.0.1+.

log_bin mysql-binlog

Acts as the “on” switch for binary logging. This is the name of the binary logging file on the database server. For example: mysql-binlog

Note: The name of this file doesn’t have to be mysql-binlog. If your server already specifies a log-bin entry, there’s no need to change it.

log_slave_updates 1

Indicates whether updates received by a read replica from a master server should be logged to the replica’s own binary log.

Note: This is applicable when using a read replica.


Step 3: Create a Stitch database user

Next, you’ll create a dedicated database user for Stitch. This will ensure Stitch is visible in any logs or audits, and allow you to maintain your privilege hierarchy.

To create a database user for Stitch, run the following command when logged into MySQL:

CREATE USER '[stitch_username]'@'localhost' IDENTIFIED BY '[password]';
GRANT SELECT, REPLICATION CLIENT, REPLICATION SLAVE ON *.* TO '[stitch_username]';

Replace [password] with a secure password. If using SSH, this can be different than the SSH password.

If you wish to restrict this user from accessing data in specific databases, tables, or columns, you can instead run GRANT queries that only allow access to the data you permit.

See the Privileges list tab for an explanation of why these permissions are required by Stitch.

In the table below are the database user privileges Stitch requires to connect to and replicate data from a MySQL database.

Privilege name Reason for requirement
SELECT

Required to select rows from tables in a database.

REPLICATION CLIENT

Required for binlog replication. Required to use SHOW BINARY LOGS, which determines that a binary log exists.

REPLICATION SLAVE

Required for binlog replication. Required to use SHOW MASTER STATUS, which fetches the current binlog file and position on the server.


Step 4: Retrieve server IDs

When Stitch connects to your database and uses Log-based Replication, a unique server ID will be required. This ID ensures that the integration - or integrations, if you’re connecting multiple databases - will not encounter conflicts during the replication process.

To avoid conflicts, you’ll check which server IDs are currently in use and then define a new, unqiue ID in Stitch.

  1. Log into the MySQL server that acts as the replication master.
  2. Run the following statement:

    mysql> SHOW SLAVE HOSTS;
    
  3. The SHOW SLAVE HOSTS statement will return information about servers that are or have been connected as replication slaves:

    +------------+-------------+------+-----------+------------+
    | Server_id  | Host        | Port | Master_id | Slave_UUID |
    +------------+-------------+------+-----------+------------+
    | 192168010  | stitch_prod | 3306 | 192168011 | <UUID>     |
    | 1921680101 | stitch_dev  | 3306 | 192168011 | <UUID>     |
    +------------+-------------+------+-----------+------------+
    

In the next step, you’ll define a unique server ID for your Stitch MySQL integration to use.


Step 5: Connect Stitch

  1. Sign into your Stitch account, if you haven’t already.
  2. On the Stitch Dashboard page, click the Add Integration button.
  3. Click the MySQL icon.
  4. Fill in the fields as follows:

    • Integration Name: Enter a name for the integration. This is the name that will display on the Stitch Dashboard for the integration; it’ll also be used to create the schema in your data warehouse.

      For example, the name “Stitch MySQL” would create a schema called stitch_mysql in the data warehouse. Note: The schema name cannot be changed after the integration is saved.

    • Host (Endpoint): Enter the host address (endpoint) used by the MySQL instance.

      In general, this will be 127.0.0.1 (localhost), but could also be some other network address (ex: 192.68.0.1) or your server’s public IP address. Note: This must be the actual address - entering localhost into this field will cause connection issues.

    • Port: Enter the port used by the MySQL instance. The default is 3306.

    • Username: Enter the Stitch MySQL database user’s username.

    • Password: Enter the password for the Stitch database user.

    • Database: Optional: Enter the name of the default database Stitch will connect to. Stitch will ‘find’ all databases you give the Stitch user access to - a default database is only used to test and complete the connection.

    • Server ID: Optional: Enter the unique server ID of instance you’re connecting to Stitch.

      This can be any numeric value within MySQL’s accepted server ID range, as long as it’s unique to the instance. For example: If in the Retrieve Server IDs step there are servers with the IDs 192168010 and 1921680101, you can enter any other numbers in this field.

Enter SSH connection details

If you’re using an SSH tunnel to connect your MySQL database to Stitch, you’ll also need to complete the following:

  1. Click the SSH Tunnel checkbox.

  2. Fill in the fields as follows:

    • SSH Host: Enter the IP address or hostname of the server Stitch will SSH into.

    • SSH Port: Enter the SSH port on your server. (22 by default)

    • SSH User: Enter the Stitch Linux (SSH) user’s username.

In addition, click the Connect using SSL checkbox if you’re using an SSL connection. Note: The database must support and allow SSL connections for this setting to work correctly.


Step 6: Create a replication schedule

In the Replication Frequency section, you’ll create the integration’s replication schedule. An integration’s replication schedule determines how often Stitch runs a replication job, and the time that job begins.

Stitch offers two methods of creating a replication schedule:

  • Replication Frequency: This method requires selecting the interval you want replication to run for the integration. Start times of replication jobs are based on the start time and duration of the previous job. Refer to the Replication Frequency documentation for more information and examples.
  • Anchor scheduling: Based on the Replication Frequency, or interval, you select, this method “anchors” the start times of this integration’s replication jobs to a time you select to create a predictable schedule. Anchor scheduling is a combination of the Anchor Time and Replication Frequency settings, which must both be defined to use this method. Additionally, note that:

    • A Replication Frequency of at least one hour is required to use anchor scheduling.
    • An initial replication job may not begin immediately after saving the integration, depending on the selected Replication Frequency and Anchor Time. Refer to the Anchor Scheduling documentation for more information.

    • You’ll need to contact support to request using an Anchor Time with this integration.

To help prevent overages, consider setting the integration to replicate less frequently. See the Understanding and Reducing Your Row Usage guide for tips on reducing your usage.


Step 7: Select data to replicate

The last step is to select the tables and columns you want to replicate. When you track a table, you’ll also need to define its Replication Method and, if using Key-based Incremental Replication, its Replication Key.

You can track tables and columns by:

  1. In the Integration Details page, click the Tables to Replicate tab.
  2. Locate a table you want to replicate.
  3. Click the checkbox next to the object’s name. A green checkmark means the object is set to replicate.
  4. If there are child objects, they’ll automatically display and you’ll be prompted to select some.
  5. After you set a table to replicate, the Table Settings page will display. Note: When you track a table, by default all columns will also be tracked.
  6. In the Table Settings page, define the table’s Replication Method and, if using Key-based Incremental Replication, its Replication Key.

  7. Repeat this process for every table you want to replicate.

  8. Click the Finalize Your Selections button to save your data selections.

Initial and historical replication jobs

After you finish setting up MySQL, its Sync Status may show as Pending on either the Stitch Dashboard or in the Integration Details page.

For a new integration, a Pending status indicates that Stitch is in the process of scheduling the initial replication job for the integration. This may take some time to complete.

Free historical data loads

The first seven days of replication, beginning when data is first replicated, are free. Rows replicated from the new integration during this time won’t count towards your quota. Stitch offers this as a way of testing new integrations, measuring usage, and ensuring historical data volumes don’t quickly consume your quota.


Extracting data from MySQL

When you connect a database as an input, Stitch only needs read-only access to the databases, tables, and columns you want to replicate. There are two processes Stitch runs during the Extraction phase of the replication process: a structure sync and a data sync.

Structure syncs

This is the first part of the Extraction process. During this phase, Stitch will detect any changes to the structure of your database. For example: A new column is added to one of the tables you set to replicate in Stitch. Structure syncs are how Stitch identifies the databases, tables, and columns to display in the Stitch app.

Stitch runs the following queries on MySQL databases to perform a structure sync:

  • SHOW DATABASES
  • SHOW TABLES FROM [database_name]
  • SHOW KEYS FROM [table_name]
  • SELECT * FROM INFORMATION_SCHEMA.TABLES

Data syncs

This is the second part of the Extraction process. During this phase, Stitch extracts data from the source and replicates it. The method Stitch uses is the same for all databases, but differs depending on the Replication Method that each table uses.

The tabs below contain info about the queries Stitch runs during the data syncs for each type of Replication Method supported for MySQL integrations.

Data syncs for tables using Key-based Incremental

Initial (historical) replication jobs

During the initial replication job for a table using Key-based Incremental Replication, Stitch will replicate the table in full by running a SELECT query and read out of the resulting cursor in batches:

  SELECT column_a, column_b <,...>
    FROM table_a
ORDER BY replication_key_column
Ongoing replication jobs

During subsequent jobs, Stitch will use the last saved maximum value of the Replication Key column to identify new and updated data.

Stitch will run the following query and read out of the associated cursor in batches:

  SELECT column_a, column_b <,...>
    FROM table_a
   WHERE replication_key_column >= 'last_maximum_replication_key_value'
ORDER BY replication_key_column

Data syncs for tables using Log-based Incremental

Initial (historical) replication jobs

During the initial replication job for a table using Log-based Incremental Replication, Stitch will use a SELECT query to retrieve all data for the table and then read out of the resulting cursor in batches:

SELECT column_a, column_b <,...>
  FROM table_a
Ongoing replication jobs

During subsequent jobs, Stitch will use the database's binary logs to stream updates.

Stitch will 'bookmark' its position in the binary log at the end of each replication job, allowing it to resume at the correct position during the next extraction.

Data syncs for tables using Full Table

For tables using Full Table Replication, Stitch runs a single query and reads out of the resulting cursor in batches:

SELECT column_a, column_b <,...>
  FROM table_a

This query will be run for each table using Full Table Replication during every replication job, whether it's the initial historical job or a subsequent job.

Recommendations

While we make every effort to ensure the queries that Stitch executes don’t impart significant load on your databases, we still have some recommendations for guaranteeing database performance:

  • Use a replica database instead of connecting directly. We recommend using read replicas in lieu of directly connecting production databases with high availability and performance requirements.
  • Apply indexes to Replication Key columns. We restrict and order our replication queries by this column, so applying an index to the columns you’re using as Replication Keys can improve performance.

Questions? Feedback?

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