The query and analysis function of Log Service supports analyzing logs by using mathematical statistics functions. The specific statements and meanings are as follows.

Statements  Meaning Example 
corr(y, x) Returns the correlation coefficient of two columns. The result is from 0 to 1. latency>100| select corr(latency,request_size)
covar_pop(y, x)   Calculates the population covariance.  latency>100| select covar_pop(request_size,latency)
covar_samp(y, x) Calculates the sample covariance. Latency> 100 | select covar_samp(request_size,latency)
regr_intercept(y, x) Returns the linear regression intercept of input values. y is the dependent value.  x is the independent value. latency>100| select regr_intercept(request_size,latency)
regr_slope(y,x) Returns the linear regression slope of input values. y is the dependent value.  x is the independent value. latency>100| select regr_slope(request_size,latency)
stddev(x) or stddev_samp(x) Returns the sample standard deviation of column x. latency>100| select stddev(latency)
stddev_pop(x) Returns the population standard deviation of column x. latency>100| select stddev_pop(latency)
variance(x) or  Var_samp (X) Calculates the sample variance of column x. latency>100| select variance(latency)
var_pop(x) Calculates the population variance of column x. latency>100| select variance(latency)