AVG
Description
Syntax
AVG([DISTINCT] expr)
Used to return the average value of the selected field
Optional field DISTINCT parameters can be used to return the weighted average
example
mysql> SELECT datetime, AVG(cost_time) FROM log_statis group by datetime;
+---------------------+--------------------+
| datetime | avg(`cost_time`) |
+---------------------+--------------------+
| 2019-07-03 21:01:20 | 25.827794561933533 |
+---------------------+--------------------+
mysql> SELECT datetime, AVG(distinct cost_time) FROM log_statis group by datetime;
+---------------------+---------------------------+
| datetime | avg(DISTINCT `cost_time`) |
+---------------------+---------------------------+
| 2019-07-04 02:23:24 | 20.666666666666668 |
+---------------------+---------------------------+
keywords
AVG