• Oracle (day 4)


    1、 Distinct Syntax format: select distinct column name from table name 2、 Statistical function avg(x) count(1) count(*) max(x) min(x) sum(x) StdDev (x) to find the standard deviation of the value of X in a group of rows Variance (x) find the variance of x value in a group of rows Round and TRUNC: select round(avg(sal),4) […]