When connecting to a Snowflake database and expanding its Schemas node, the following error may occur:

JDBC driver internal error: exception creating result java.lang.NoClassDefFoundError: Could not initialize class net.snowflake.client.jdbc.internal.apache.arrow.memory.RootAllocator

This error occurs whenever Snowflake's JDBC driver fails to load Arrow, a library that it uses as the default way to communicate with the database server. Snowflake's own Knowledge Base has an article on the subject.


If this error is encountered, it can be circumvented by disabling the use of Arrow altogether. This can be done by disconnecting from the database, opening its Properties tab, selecting the Connection Hooks page and enabling Run SQL at Connect. In the textbox, add the following line:

ALTER SESSION SET JDBC_QUERY_RESULT_FORMAT='JSON';

Clicking Apply and reconnecting to the database should resolve the issue.