注释：查询该课程表下,所有的课程以及课程观看的人数统计
SELECT ml.`name` as lessonName,ml.category,ml.deleted,ml.teacherName,
ml.id,ml.liveId,ml.selected,mlc.channelId,p.viewNums,count(*) as totalNum
from mlk_live_channel AS ml
LEFT JOIN mlk_lesson_channel AS mlc ON mlc.lessonId = ml.id
LEFT JOIN mlk_live_channel AS mcl ON mcl.id = mlc.channelId
LEFT JOIN
(SELECT mpr.liveId,mpr.memberId,COUNT(mpr.liveId) as viewNums FROM mlk_payment_record AS mpr
WHERE mpr.payType = 3 AND mpr.notify = 1 GROUP BY mpr.liveId) AS p
ON p.liveId = mcl.liveId
WHERE ml.deleted = 0 AND ml.category = 1
GROUP BY ml.id
ORDER BY ml.create_time
$connection = $this->db;
$sql = "SELECT ml.name as lessonName,ml.category,ml.deleted,ml.teacherName,ml.banner,
ml.id,ml.liveId,ml.selected,mlc.channelId,p.viewNums,count(mlc.lessonId) as totalLesson
from mlk_live_channel AS ml
LEFT JOIN mlk_lesson_channel AS mlc ON mlc.lessonId = ml.id
LEFT JOIN mlk_live_channel AS mcl ON mcl.id = mlc.channelId
LEFT JOIN
(SELECT mpr.liveId,mpr.memberId,COUNT(mpr.liveId) as viewNums FROM mlk_payment_record AS mpr
WHERE mpr.payType = 3 AND mpr.notify = 1 GROUP BY mpr.liveId) AS p
ON p.liveId = mcl.liveId
WHERE ml.deleted = 0 AND ml.category = 1
GROUP BY ml.id
ORDER BY ml.create_time";
$totals = $connection->fetchAll($sql);
$this->view->setVar('channles', $totals);
SELECT ml.`name` as lessonName,ml.category,ml.deleted,ml.teacherName,mlc.channelId,ml.liveId,ml.banner,
ml.id,ml.selected,mlc.channelId,SUM(p.viewNums) as totalViews,COUNT(mlc.lessonId) AS totalLesson
from mlk_live_channel AS ml
LEFT JOIN mlk_lesson_channel AS mlc ON mlc.lessonId = ml.id
LEFT JOIN
(SELECT mlc.id,mlc.liveid,count(DISTINCT mpr.memberId) as viewNums
FROM mlk_live_channel AS mlc
LEFT JOIN mlk_payment_record AS mpr ON mpr.liveId = mlc.liveId
WHERE mlc.deleted = 0 and mlc.category = 2 AND mpr.payType = 4
GROUP BY mlc.liveId ) AS p
ON p.id = mlc.channelId
WHERE ml.deleted = 0 AND ml.category = 1
GROUP BY ml.id
HAVING SUM(p.viewNums)>0