sql - MySQL query to determine classes remaining or completed -

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i have following data in webinar_timing table in mysql database

start_time , end_time of type datetime

     id  | webinar_id | start_time            | end_time -------------------------------------------------------------------     1  |     5      | 3/18/2015  6:00:00 pm | 3/18/2015  7:00:00 pm     2  |     5      | 3/19/2015  6:00:00 pm | 3/19/2015  7:00:00 pm     3  |     5      | 3/20/2015  6:00:00 pm | 3/20/2015  7:00:00 pm     4  |     5      | 3/21/2015  6:00:00 pm | 3/21/2015  7:00:00 pm     5  |     5      | 3/22/2015  6:00:00 pm | 3/22/2015  7:00:00 pm     6  |    11      | 3/20/2015  8:00:00 pm | 3/20/2015  9:00:00 pm     7  |    11      | 3/21/2015  8:00:00 pm | 3/21/2015  9:00:00 pm     8  |    11      | 3/22/2015  8:00:00 pm | 3/22/2015  9:00:00 pm     9  |    22      | 3/25/2015  8:00:00 pm | 3/25/2015  9:00:00 pm    10  |    22      | 3/27/2015  8:00:00 pm | 3/27/2015  9:00:00 pm    11  |    22      | 3/29/2015  8:00:00 pm | 3/27/2015  9:00:00 pm

basically, each webinar, want total occurences , number of classes completed or remaining , next upcoming class

egs: when run query @ 3/21/2015 @ 4:00 pm - result expecting

  webinar_id | total     | classes completed | next class ----------------------------------------------------------      5      |   5       | 3                 | 3/21/2015  6:00:00 pm     11      |   3       | 1                 | 3/21/2015  8:00:00 pm     22      |   3       | 0                 | 3/25/2015  8:00:00 pm

or

  webinar_id | total     | classes remaining | next class ----------------------------------------------------------      5      |   5       | 2                 | 3/21/2015  6:00:00 pm     11      |   3       | 2                 | 3/21/2015  8:00:00 pm     22      |   3       | 3                 | 3/25/2015  8:00:00 pm

any appreciated in advance

just use sum(if(...))

select webinar_id, count(*) total,  sum(if(end_time<now(), 1, 0)) completed,  sum(if(start_time>=now(), 1, 0)) remaining webinar_times group webinar_id;

you'll have figure out whether looking @ start_time or end_time , equals , little details that...


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