This Oracle tutorial explains how to use the Oracle/PLSQL COVAR_POP function.
The Oracle/PLSQL COVAR_POP function returns the population covariance of a set of number pairs.
The syntax for the Oracle/PLSQL COVAR_POP function is:
COVAR_POP( expression1, expression2 )
expression1 and expression2 are numeric expression.
The COVAR_POP function ignores all pairs where expression1 or expression2 has a null value.
select owner, COVAR_POP(avg_row_len, avg_space) from all_tables group by owner;