SQL Reference - VAR

VAR_POP(expression)

expression: This represents the set of values, a column in the table, for which the population variance is calculated.

Example

SELECT VAR_POP(column_name) FROM table_name;

Output

0.25

Explanation

The VAR_POP() function in SQL is used to return the population variance of a set of values. The example code would return the population variance of the specified column values from the specified table. The output shows a sample return value of the variance.

VAR_POP(expression)

expression: This is the column or set of data for which the population variance is to be calculated. It can either be a numeric data type or a set of numeric values which is derived from numeric data.

Example

SELECT VAR_POP(sal)
FROM emp;

Output

VAR_POP(SAL)
------------
50.5

Explanation

The VAR_POP function in the code returns the population variance of salary (sal), calculated from the entire set of selected records in the emp table. This can be useful when statistical variance of a particular column’s data is required for analysis.

VAR_POP(expression)

expression: This is the column or set of values that the function will be applied to. VAR_POP function computes the population variance of a set of numbers, so the expression will usually be a specific column containing numerical data in the database table.

Example

CREATE TABLE scores (score INTEGER);
INSERT INTO scores VALUES (4),(5),(6),(7);
SELECT VAR_POP(score) AS variance_population FROM scores;

Output

 variance_population
---------------------
 1.25
(1 row)

Explanation

VAR_POP() function computes the population variance of a set of numbers. Here it’s used to calculate the population variance of the ‘score’ in the ‘scores’ table. The result 1.25 is the variance of the population of the scores 7.