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    E-MapReduce:Configure connectors

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    E-MapReduce:Configure connectors

    Last Updated:Jul 18, 2026

    E-MapReduce (EMR) Presto provides several built-in connectors for querying external data sources. You can modify these connectors or add custom ones.

    Built-in connectors

    EMR Presto includes the following built-in connectors.

    Connector

    Function

    hive

    Queries data stored in a Hive data warehouse.

    kudu

    Queries, inserts, and deletes data stored in Kudu.

    mysql

    Queries and creates tables in an external MySQL instance.

    iceberg

    Queries data files stored in the Iceberg format.

    hudi

    Queries Copy-on-Write (COW) and Merge-on-Read (MOR) tables.

    delta

    Queries Delta Lake tables.

    jmx

    Provides system monitoring and debugging capabilities.

    system

    Queries basic information and metrics about the cluster.

    Note

    The system connector requires no configuration. All information is available in the system directory.

    Modify a built-in connector

    To modify a built-in connector, modify its configuration file on the Configure page of the Presto service in the EMR console and then restart the service.

    Parameter

    Configuration file

    hive-hadoop2

    hive.properties

    kudu

    kudu.properties

    mysql

    mysql.properties

    iceberg

    iceberg.properties

    hudi

    hudi.properties

    delta

    delta.properties

    jmx

    jmx.properties

    Example: Modify the Hive connector

    1. In the EMR console, go to the Configure page of the Presto service. In the Service Configuration area, click the hive.properties tab.

    2. Modify the configuration items as needed.

      For details about modifying configuration items, see Manage configuration items.

    3. After you save the configuration, choose More > Restart in the upper-right corner.

      Important

      The changes take effect after you restart the service.

    Add a custom connector

    EMR Presto provides five placeholder connectors (connector1 through connector5) for adding custom connectors. They correspond to the connector1.properties, connector2.properties, connector3.properties, connector4.properties, and connector5.properties files on the Configure page of the Presto service. You can configure a placeholder connector in the same way as a built-in connector.

    To add a custom connector, configure an unused placeholder connector.

    Example: Add a MongoDB connector

    1. In the EMR console, go to the Configure page of the Presto service. In the Service Configuration area, click the connector1.properties tab.

    2. Set connector.name to mongodb.

    3. Add custom configuration items as needed.

      For details about adding configuration items, see Modify configuration items.

    4. After you save the configuration, choose More > Restart in the upper-right corner.