VARIANCE,VAR_POP,VARIANCE_POP

description

Syntax

VARIANCE(expr)

返回expr表达式的方差

example

1. MySQL > select variance(scan_rows) from log_statis group by datetime;
2. +-----------------------+
3. | variance(`scan_rows`) |
4. +-----------------------+
5. |    5.6183332881176211 |
6. +-----------------------+

8. MySQL > select var_pop(scan_rows) from log_statis group by datetime;
9. +----------------------+
10. | var_pop(`scan_rows`) |
11. +----------------------+
12. |   5.6230744719006163 |
13. +----------------------+

keyword

VARIANCE,VAR_POP,VARIANCE_POP,VAR,POP