Please append a semicolon ";" at the end of the query and enter your query in a single line to avoid error.
SELECT o.order_id, c.customer_name FROM orders o JOIN customers c ON o.customer_id = c.customer_id; ...
Abstract: Extremely large-scale multiple-input-multiple-output (XL-MIMO), which offers vast spatial degrees of freedom, has emerged as a potentially pivotal enabling technology for the sixth ...