@glevin , That is unfortunate. Here are few other options you could try

1. Please ensure you are using latest version of the JDBC driver

2. Try setting the fetch size before the query execution instead of the url as below

SET spark.databricks.jdbc.fetchsize = 5000;
SELECT * FROM my_table;

3. If you are open to using Rest API, it would help in getting all the records.

Reference links for API: https://docs.databricks.com/api/workspace/introduction

https://docs.databricks.com/api/workspace/statementexecution/executestatement