message: maybe this fixes having issues to reproduce
diff: @@ -19,6 +19,8 @@ public class DuckDBStatement implements Statement {
  }
  public boolean execute(String sql) throws SQLException {
  + result = null;
  + stmt_ref = null;
  stmt_ref = DuckDBNative.duckdb_jdbc_prepare(conn.conn_ref, sql);
  Object[] params = {};
  ByteBuffer result_ref = DuckDBNative.duckdb_jdbc_execute(stmt_ref, params);
  @@ -54,6 +56,7 @@ public class DuckDBStatement implements Statement {
  stmt_ref = null;
  }
  conn = null;
  + result = null;
  }
  protected void finalize() throws Throwable {
  