mysql - #2013 - 当我运行此查询时，在查询期间丢失了与 MySQL 服务器的连接

Question

SELECT
    contact_list.id,
    contact_list.contact_number,
    call_history.id,
    call_history.user_id,
    call_history.contact_number,
    call_history.call_type,
    call_history.call_duration,
    call_history.call_date,
    call_history.call_time,
    call_history.audio_file,
    employees.username
FROM
    call_history
JOIN contact_list ON contact_list.contact_number = call_history.contact_number
JOIN employees ON employees.id = call_history.user_id
WHERE
    call_history.id IN(
    SELECT
        MAX(call_history.id)
    FROM
        call_history
    WHERE
        1 AND employees.username LIKE '%bha%'
    GROUP BY
        call_history.contact_number
)
ORDER BY
    call_history.id
DESC

Answer 1

您可以尝试设置 max_allowed_pa​​cket 变量并再次运行查询吗？

mysql> set global max_allowed_packet=104857600;
Query OK, 0 rows affected (0.00 sec)

mysql> 

或者您可以使用 https://dev.mysql.com/doc/refman/5.7/en/error-lost-connection.html 调试原因