Virtual Schema Logging

This article explains how to use the netcat tool in Linux to retrieve logs when you require support for a virtual schema.

Remote logging for virtual schemas requires that you use one of the supported Exasol virtual schema adapters. If you are building your own adapter you must include the following libraries:

For more information, see Adapters and Properties and the Virtual Schema Github repository.

The following steps only apply to adapters created by Exasol.

  1. Start netcat in listen mode on a free TCP port on a machine that is reachable from an Exasol cluster.

    nc -lkp 3000

  2. Run the following command to find your IP address.

    ip -br address

  3. Create or alter your virtual schema and add the properties DEBUG_ADDRESS and LOG_LEVEL. For more details, see CREATE SCHEMA or ALTER SCHEMA. Replace the IP Address and port with the values from the previous steps.

    CREATE VIRTUAL SCHEMA VIRTUAL_EXASOL 
    USING SCHEMA_FOR_VS_SCRIPT.ADAPTER_SCRIPT_EXASOL WITH
        CONNECTION_NAME = 'JDBC_CONNECTION'
        SCHEMA_NAME     = '<schema name>'
        IMPORT_FROM_EXA = 'true'
        EXA_CONNECTION  = 'EXA_CONNECTION'
        DEBUG_ADDRESS   =  '<IP Address>:<Port>' 
        LOG_LEVEL       =  'ALL';

    The parameter LOG_LEVEL specifies the log level defined in Java Utility Logging Levels.

  4. The following message is shown in case of a successful connection.

    Attached to output service