Question

mysql> select calendar.calId,calendar.cdate,lsUsers.userId,
              apptActual.OPDID,count(*) 
        from calendar 
        LEFT JOIN apptActual on calendar.calId=apptActual.calendarId
        LEFT JOIN lsUsers on lsUsers.userId=apptActual.OPDID 
        group by 1,2,3,4 order by 3
        desc limit 10;

结果是：

+-------+------------+--------+-------+----------+
| calId | cdate      | userId | OPDID | count(*) |
+-------+------------+--------+-------+----------+
|    76 | 2016-03-16 |     11 |    11 |        1 |
|    75 | 2016-03-15 |     11 |    11 |        1 |
|    77 | 2016-03-17 |      9 |     9 |        1 |
|    75 | 2016-03-15 |      8 |     8 |        1 |
|    75 | 2016-03-15 |      1 |     1 |        1 |
|  1279 | 2019-07-02 |   NULL |  NULL |        1 |
|  1287 | 2019-07-10 |   NULL |  NULL |        1 |
|  1295 | 2019-07-18 |   NULL |  NULL |        1 |
|  1303 | 2019-07-26 |   NULL |  NULL |        1 |
|  1311 | 2019-08-03 |   NULL |  NULL |        1 |
+-------+------------+--------+-------+----------+
10 rows in set (0.34 sec)

通过使用上面的查询我得到的结果如上，但我需要结果如下（所有userId必须来。）

+-------+------------+--------+-------+----------+
| calId | cdate      | userId | OPDID | count(*) |
+-------+------------+--------+-------+----------+
|    76 | 2016-03-16 |     11 |    11 |        1 |
|    75 | 2016-03-15 |     11 |    11 |        1 |
|    77 | 2016-03-17 |      9 |     9 |        1 |
|    75 | 2016-03-15 |      8 |     8 |        1 |
|    75 | 2016-03-15 |      1 |     1 |        1 |
|  1279 | 2019-07-02 |      4 |  NULL |        1 |
|  1287 | 2019-07-10 |      21|  NULL |        1 |
|  1295 | 2019-07-18 |      3 |  NULL |        1 |
|  1303 | 2019-07-26 |      7 |  NULL |        1 |
|  1311 | 2019-08-03 |      5 |  NULL |        1 |
+-------+------------+--------+-------+----------+

请建议我如何获得上述结果！

Answer 1

如果你在userId = appActual.OPDID上加入lsUsers，你会得到你所要求的：usedId（NULL）= OPDID（NULL）。有没有其他方式加入lsUsers？

获取所需的sql查询结果

1 个答案: