​​​​​​​Note – MySQL is supported as a Source Database since version 6, by Repstance Advanced Edition only (see Supported Database Requirements).

The following parameters are valid for the MySQL Capture Process. The Capture Process reads the binary log of the server; the settings of the server and of the database are described in MySQL as Source.

Process Parameters

• process – The only possible value is capture
• id – The Capture Process id
• dbtype – The value is mysql
• name – Name of the Capture Process. It is the first part of the names of its trail files and cannot be changed later

Database Connectivity

• server – Host name or IP address of the MySQL server
• port – Database port. The default value is 3306
• dbname – The database to connect to. It is optional
• user – Database User name. The Capture Process needs the privileges REPLICATION SLAVE and REPLICATION CLIENT on all databases to read the binary log, and SELECT on the tables to be replicated. The Initial Load also needs LOCK TABLES on them (see Database Privileges)
• password – Database User password

DML/DDL Replication Objects Specification

• ddlinclude – Mask of the tables whose DDL is captured. Nothing is captured unless it is listed
• ddlexclude – Mask of the tables whose DDL is skipped by the Capture Process
• dmlinclude – Mask of the tables whose changes (INSERT, UPDATE and DELETE) are captured. Nothing is captured unless it is listed
• dmlexclude – Mask of the tables whose changes are skipped by the Capture Process
• skiploopback – Specifies which changes made by Apply Processes the Capture Process skips, so that they are not replicated back in a two-way replication. The DDL statements of the Apply Processes are skipped by the Capture Process; their rows are skipped by the parameter skiploopback of the Apply Process. The Apply Processes are given by their ids, separated by commas. The value all is all of them, the value none is none of them. The default value is all
• map – The set of the parameters to determine global objects’ transformation

In MySQL the first part of schema.table is the name of the database that holds the table. See Capture Objects Specification for the DML and DDL objects specification details and Objects Mapping and Possible Transforms for the objects’ transformation details.

Initial Load Objects Specification

• loadinclude – Mask of the tables to be included into the Initial Load, with the optional load option, filter and chunk: schema.table[:option[:filter[:chunk]]]. The options are A (load the rows and keep the rows that the table has, the default), D (delete the rows first), T (truncate first), C (create the table), R (recreate the table) and M (merge)
• loadexclude – Mask of the tables to be skipped during the Initial Load

See chapter Initial Load for more details.

Note – The Initial Load of a table reads the rows as they were at one position of the binary log, and the changes after that position are read from the binary log, so no change is lost or applied twice. To find the position the Capture Process locks the table for reading for a short time, until the snapshot has been taken. A table of an engine other than InnoDB has no snapshot and stays locked until its last row has been read.

Performance Tuning Parameters

• readrows – Number of the rows of changes which the Capture Process holds at once. A transaction larger than this number is sent and written to the trail files in parts. A smaller value reduces the memory usage of the Capture Process, a larger value reduces the number of cycles. The value must have at least 3 digits. The default value is 150000
• maxtrailbytes – Size, in bytes, after which the Capture Process closes the current trail file and starts the next one. A trail file can be larger than this size by the size of the last written batch. The default value is 52428800 (50 MiB)

Note – A very small value results in a large number of small trail files.

Other Parameters

• includecomputedcols – Determines if the generated columns of the Source tables are included into the list of the replicated columns. The possible values are:
  • 0 – do not include the generated columns (default value)
  • 1 – include the generated columns
• pollingdelay – The number of seconds the Capture Process waits after each cycle, to ease the load on the Source Database. The default value is 0
• preview – This parameter is used to validate the list of the tables to be included into the replication along with the transformation rules. The possible values are:
  • 0 – do not use “preview” mode (default)
  • 1 – do not apply the configuration to the Capture Process but provide the list of the tables to be included into the replication along with the transformation
• autostart – Determines if the Process must be run automatically. The possible values are:
  • 0 – do not run the Process automatically (default value)
  • 1 – run the Process automatically, when the server starts and when the process is created
• restartattempts – Number of attempts to restart the failed Capture Process automatically. The server checks the processes every 5 minutes. The value 0 disables the automatic restart. When the attempts are used up, the notification channels (see the notification parameter) are informed. The default value is 5. The number of attempts is restored to the full value as soon as the process makes progress after a failure
• notification – The ids of the notification channels, separated by comma (see Monitoring Replication for the details on the channels), which are informed by e-mail when the process has failed and can not be restarted automatically any more. By default nobody is notified
• debuglevel – The level of debugging, possible values are 0-16, the default value is 0

The parameters secondary, cdcrestart and minimizepayload of the SQL Server Capture Process do not exist for MySQL and are refused.

Note – The DDL statements that the Capture Process reads are recorded in the dictionary of the trail. An Apply Process for a Target Database of another type than MySQL needs ddlprocessing=dictionary (see Prepare Apply Process).

Examples

Add a Capture Process that captures the changes and the DDL of the tables of the schema sales and copies them at the first start:

Show the parameters of the process and change the Initial Load list:

A parameter that belongs to another type of Source Database is refused, and the reply lists the valid ones:

Check the connection and the objects of the process:

See Validate Process for the checks, and Remove Process to remove the process.