Oracle SQL - COVAR_SAMP function

Introduction

COVAR_SAMP function returns a sample covariance between expr1 and expr2, and the general format is:

COVAR_SAMP(expr1, expr2)

Given the following table.

Demo

SQL>
SQL> drop table my_table;

Table dropped.--   w  w  w  .  jav  a 2s  .co m

SQL> create table my_table(
  2  x      NUMBER(4)  primary key,
  3  y      NUMBER(4)  not null);
SQL>
SQL> insert into my_table values(1,2);
SQL> insert into my_table values(2,4);
SQL> insert into my_table values(3,6);
SQL> insert into my_table values(4,9);
SQL> insert into my_table values(5,13);
SQL> insert into my_table values(6,16);
SQL> insert into my_table values(7,20);
SQL> insert into my_table values(8,27);
SQL> insert into my_table values(9,32);
SQL> insert into my_table values(10,47);
SQL> insert into my_table values(11,53);
SQL> insert into my_table values(12,60);
SQL> insert into my_table values(13,76);
SQL> insert into my_table values(14,100);
SQL> insert into my_table values(15,130);
SQL> insert into my_table values(16,189);
SQL> insert into my_table values(17,300);
SQL> insert into my_table values(18,789);
SQL> insert into my_table values(19,1000);
SQL>

Demo

SQL>
SQL> SELECT COVAR_SAMP(y, x) FROM my_table;

COVAR_SAMP(Y,X)-- from   w w w . j a  v  a 2 s  . c o  m
---------------
       01087.56

SQL>