Sql average

Sql count

/*COUNT(column_name) will return the number of rows from the column 
that are not NULL*/
SELECT COUNT(column_name)
FROM table_name;

/*COUNT(*) will return the number of rows from the table*/
SELECT COUNT(*)
FROM table_name;

Sql average

SELECT student_name, avg(notes) FROM student_notes GROUP BY student_name;

How to find average in sql

SELECT FIRST_NAME FROM EMPLOYEES
WHERE SALARY = (SELECT AVG(SALARY) FROM EMPLOYEES);

Similar codes

0 vote162 views1 answer
Select distinct after join
SQL
1 vote144 views1 answer
Set all the vluses in calumn in sql to false
SQL
1 vote163 views1 answer
Blob datatype in mysql
SQL
2 votes164 views1 answer
Power query concatenate
SQL
0 vote146 views1 answer
Oarcale list objects
SQL
0 vote146 views1 answer
View t-sql mail configuration
SQL
0 vote184 views1 answer
Sql server delete records with specific date
SQL
0 vote151 views1 answer
Alasql delete column
SQL
0 vote150 views1 answer
Sql server alter table column nullable
SQL
1 vote186 views2 answers
Install sql server management studio ubuntu
SQL