Mean and mode in SQL Server

Problem Statement

Mean is the average of a given data set, calculated by dividing the sum by the number of values ​​in the data set.

The mode of the data set is the value that appears most frequently in a series of data

If our data set is {1, 2, 3, 4}, the average value is − (1 2 3 4) / 4 = 2.5

If our data set is {1, 2, 3, 4, 1, 1, 1, 1}, the mode is − 1 because it occurs 5 times .

Example

• First, create a table-

CREATE TABLE NUMBERS (
   value INT
)

• Insert data into the table-

INSERT INTO NUMBERS VALUES (1);
INSERT INTO NUMBERS VALUES (2);
INSERT INTO NUMBERS VALUES (3);
INSERT INTO NUMBERS VALUES (4);

• Use the following query to find the mean -

SELECT AVG(val) FROM NUMBERS;

• Insert pattern-less rows with duplicate values-

INSERT INTO NUMBERS VALUES (1);
INSERT INTO NUMBERS VALUES (1);
INSERT INTO NUMBERS VALUES (1);
INSERT INTO NUMBERS VALUES (1);

• Use the following query to find the pattern -

SELECT TOP 1 val
FROM NUMBERS
GROUP BY val
ORDER BY COUNT(*) DESC

The above is the detailed content of Mean and mode in SQL Server. For more information, please follow other related articles on the PHP Chinese website!