@Rocky after update from 4.0.8 to 4.1.0, my jdbc table and my external table having this issue: SQL Error [1064] [42000]: No type checker found for Java class: java.math.BigDecimal: BE:1567985 No type checker found for Java class: java.math.BigDecimal: BE:1567985 this not happen in 4.0.8

The error you're encountering,

No type checker found for Java class: java.math.BigDecimal

, is due to a change in StarRocks starting from version 4.1.0 (and some recent dev versions), where the type mapping system for JDBC and external tables was migrated from hardcoded logic to a mandatory XML-based configuration. In previous versions like 4.0.8, these mappings were built-in. In 4.1.0, the BE (Backend) expects a configuration file to define how Java classes (from JDBC drivers) map to StarRocks types. Root Cause The BE is unable to find the required mapping for

java.math.BigDecimal

because the configuration file

conf/type_checker_config.xml

is either missing, inaccessible, or incomplete in your BE installation directory. How to Fix 1. Verify the configuration file exists Check if the file

type_checker_config.xml

exists in your StarRocks BE

conf

directory:

bash
ls -la $STARROCKS_HOME/conf/type_checker_config.xml

_Note: If

$STARROCKS_HOME

is not set, it defaults to the

conf/

directory relative to where the BE process started._ 2. Restore the default configuration If the file is missing (common after an upgrade if you only copied the binaries), you must copy it from the StarRocks 4.1.0 distribution package. The default file contains the necessary mapping for `BigDecimal`:

xml
<type-mapping java_class="java.math.BigDecimal" display_name="BigDecimal">
  <type-rule allowed_type="TYPE_DECIMAL32" return_type="TYPE_DECIMAL32"/>
  <type-rule allowed_type="TYPE_DECIMAL64" return_type="TYPE_DECIMAL64"/>
  <type-rule allowed_type="TYPE_DECIMAL128" return_type="TYPE_DECIMAL128"/>
</type-mapping>

3. Ensure proper permissions and pathing * Permissions: Ensure the user running the StarRocks BE process has read permissions for this XML file. * Environment: Ensure

STARROCKS_HOME

is correctly set in your environment or start scripts so the BE knows where to look for the

conf/

folder. 4. Restart BE After adding or updating the

conf/type_checker_config.xml

file, you must restart the BE nodes for the changes to take effect. Validation Check your BE logs (

<http://be.INFO|be.INFO>

or

be.WARNING

) after startup. You should see a message confirming the initialization:

INFO: TypeCheckerManager initialized from XML configuration: .../conf/type_checker_config.xml

If you see an error like

All type checkers must be defined in XML. Please ensure the configuration file exists

, it means the BE is still failing to locate the file. References • developers/type_checker_xml_configuration.md