What is difference between count (*) and Count column?

What is the difference between COUNT and COUNT (*) function?

As you've already learned, COUNT(*) will count all the rows in the table, including NULL values. On the other hand, COUNT(column name) will count all the rows in the specified column while excluding NULL values.

What is COUNT (*) used for?

COUNT(*) The COUNT(*) function returns the number of rows in a dataset using the SELECT statement. The function counts rows with NULL, duplicate, and non-NULL values.

What is the difference between COUNT COUNT distinct and COUNT (*)?

Count would show a result of all records while count distinct will result in showing only distinct count. For instance, a table has 5 records as a,a,b,b,c then Count is 5 while Count distinct is 3.

What is the difference between COUNT fieldname and COUNT (*) function explain with an example?

Count(fieldname): Do not use the size field for the resulting records. Again in simple words, COUNT(expression) evaluates an expression for each row in a group and returns the number of non-null values. So count() includes nulls, the other method doesn't. Note: COUNT(Id) in SOQL is equivalent to COUNT(*) in SQL.