SQL PHP HTML ASP JavaScript articles and free scripts to download

SQL AVG Command

AVG sql command is used to find out average value of a numeric field in a table. Now let us apply this AVG command to this table and find out the average mark obtain by all the students. The AVG command will calculate the average value of all the marks

id	name	class	mark
1	John Deo	Four	75
2	Max Ruin	Three	85
3	Arnold	Three	55
4	Krish Star	Four	60
5	John Mike	Four	60
6	Alex John	Four	55

Same way we can get the minimum value of a range of records by using SQL MIN command. Also check up SQL MAX command to get highest value of data
We will apply the AVG command here like this to the field mark

SELECT avg( mark ) FROM `student`

avg(mark)
65.0000

The command will calculate average value of marks considering all the marks of the table. We can define some header like this also.
SELECT AVG(mark) as avg_mark FROM `student`

avg_mark
65.0000

Here we can use the Group By command to find out the average mark obtained by each classes.

Related Tutorial

• SQL Group by
• MySQL Max
• MySQL Min
• MySQL Sum
• Copy data to new table
• SQL Left Join

SELECT class, avg( mark ) as avg_mark FROM `student` GROUP BY class

class	avg_mark
Four	62.5000
Three	70.0000

Please see the SQL SUM command to know the details on uses of GROUP BY command and the precautions.

We can add condition to the sql command to get our desired result. We can add one Where clause to the query to consider records for which mark is more than some value ( say 55 )

SELECT avg( mark ) as avg_mark, class FROM student where mark > 55 GROUP BY class