我会检查where子句，以便在和上使用正确的优先级

SELECT DISTINCT n.id as test_count 
FROM networks as n
INNER JOIN network_sessions AS ns ON ns.network_id = n.id
LEFT JOIN network_logs AS nl ON nl.network_session_id = ns.id AND nl.type = "ENTRANCE" AND nl.status_code = 0
WHERE 
    n.status_time BETWEEN ('2020-07-01 00:00:00' AND '2020-07-31 00:00:59') 
AND 
    nl.created_at BETWEEN ('2020-07-01 00:00:00' AND '2020-07-31 00:00:59')
GROUP BY n.id
HAVING COUNT(nl.id) >= 1;

如果没有样本数据和预期结果，这是未经测试的。可能是你要复习外文，成为一个或imho，但没有样本数据是不可能理解的

像下面这样试试

SELECT DISTINCT n.id as test_count 
FROM networks as n
INNER JOIN network_sessions AS ns ON ns.network_id = n.id
JOIN network_logs AS nl ON nl.network_session_id = ns.id 

WHERE n.status_time BETWEEN '2020-07-01 00:00:00' AND '2020-07-31 00:00:59' 
AND nl.created_at BETWEEN '2020-07-01 00:00:00' AND '2020-07-31 00:00:59'
AND nl.type = "ENTRANCE" AND nl.status_code = 0

因为网络日志至少包含1个值，所以您可以应用内部连接，而不需要count（）

此查询应返回在网络日志表中至少有一行且网络日志行的类型必须为“入口”且状态代码为0的网络数
这些条件在 ON a的子句 LEFT JOIN . 如果你真的想按它们过滤，那么使用 INNER JOIN --和/或将条件移至 WHERE 条款。
我还怀疑你想要7月份的所有行，而不仅仅是最后一天的第一分钟。所以：

SELECT DISTINCT n.id as test_count 
FROM networks n JOIN
     network_sessions ns
     ON ns.network_id = n.id JOIN
     network_logs nl
     ON nl.network_session_id = ns.id
WHERE nl.type = 'ENTRANCE' AND nl.status_code = 0 AND
      n.status_time >= '2020-07-01' AND 
      n.status_time < '2020-08-01' AND 
      nl.created_at >= '2020-07-01' AND
      nl.created_at < '2020-08-01' ;