Configuration¶

The main configuration of MyDumper is kept in /etc/mydumper.cnf by default.

--defaults-file[=/etc/mydumper.cnf]¶

Said configuration is found in sections like:

[mydumper]
[mydumper_session_variables]
[myloader]
[myloader_session_variables]

Where the defaults of mydumper, myloader and the session level variables are kept when they are executed. In the case of [myloader_session_variables] , the default setting is:

[myloader_session_variables]
SQL_MODE='NO_AUTO_VALUE_ON_ZERO' /*!40101
UNIQUE_CHECKS=0 /*!40114
FOREIGN_KEY_CHECKS=0 /*!40114

But, when you connect to MariaDB it gets replaced by:

[myloader_session_variables_mariadb]
# This setting replaces the default in the section [myloader_session_variables]. More details in #987
SQL_MODE='NO_AUTO_VALUE_ON_ZERO' /*!40101
UNIQUE_CHECKS=1 /*!40114
FOREIGN_KEY_CHECKS=0 /*!40114

--defaults-extra-file¶

Using [`database`.`table`] sections may be helpful, since you can add:

where: It receives a comparison compatible with the table definition;
limit: It receives a number and forces the SELECT statement to avoid reading more reads if it reaches the limit;
num_threads: It defines the amount of threads that will be used for the table;
object_to_export: It receives a comma delimited list with this options: SCHEMA, DATA, TRIGGER, ALL and NONE. ALL is equal to SCHEMA,DATA,TRIGGER;
columns_on_select: The list of columns in the SELECT statement will be replaced by the content of this parameter;
columns_on_insert: The columns in the INSERT statemnt will be replace by the content of this parameter;
object_to_export: It receives a comma delimited list with this options: SCHEMA, DATA, TRIGGER, ALL and NONE. ALL is equal to SCHEMA,DATA,TRIGGER;
partition_regex: It defines a regular expression to filter the partitions to export.

For example:

where = column > 20
limit = 1000
object_to_export = SCHEMA
columns_on_select = qty,price+20
columns_on_insert = qty,price