Average sql

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

1 vote365 views2 answers
Mysql filter by date mount
SQL
0 vote395 views1 answer
Drop index in sql
SQL
0 vote344 views3 answers
ChAnge TABLE name apex oracle
SQL
1 vote388 views1 answer
Replace all numbers in mysql
SQL
0 vote370 views1 answer
Max length found in mysql
SQL
0 vote348 views1 answer
Remove transient options sql wordpress
SQL
0 vote367 views1 answer
Update and keep original value sql
SQL
20 votes369 views6 answers
Creating a table in sql
SQL
9 votes396 views3 answers
Find all tables with column name
SQL
3 votes376 views1 answer
Sql timestamp to date
SQL