Oracle PL/SQL/Analytical Functions/VAR SAMP

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VAR_SAMP(expr): calculates the sample variance

SQL>
SQL>
SQL> create table TestTable (
  2    x    number primary key,
  3    y    number
  4  );
Table created.
SQL> insert into TestTable values (1, 7 );
1 row created.
SQL> insert into TestTable values (2, 1 );
1 row created.
SQL> insert into TestTable values (3, 2 );
1 row created.
SQL> insert into TestTable values (4, 5 );
1 row created.
SQL> insert into TestTable values (5, 7 );
1 row created.
SQL> insert into TestTable values (6, 34 );
1 row created.
SQL> insert into TestTable values (7, 32 );
1 row created.
SQL> insert into TestTable values (8, 43 );
1 row created.
SQL> insert into TestTable values (9, 87 );
1 row created.
SQL>
SQL> select * from TestTable;
         X          Y
---------- ----------
         1          7
         2          1
         3          2
         4          5
         5          7
         6         34
         7         32
         8         43
         9         87
9 rows selected.
SQL>
SQL> --VAR_SAMP(expr): calculates the sample variance.
SQL>
SQL> -- VAR_SAMP(expr)
SQL>
SQL> SELECT VAR_SAMP(y) FROM TestTable;
VAR_SAMP(Y)
-----------
 805.694444
SQL>
SQL> drop table TestTable;
Table dropped.
SQL>
SQL>
SQL>