Answer / guest

'Count': Counts the number of non-null values.
'Count(*)': Counts the number of rows in the table,
including null values and duplicates.

Answer / nikita

I agree with the above answer

Answer / vijay dev saxena

Count(exp): Counts the number of rows excluding null values.
Count(*) : Counts the number of rows including null and
duplicates records.

Answer / selvaraj.v

In SQL Server 2000,
Query:
------
select count from employees
Answer:
------
invalid column name 'count'


In SQL Server 2000,
Query:
------
select count(*) from employees

Answer:
-------
No column name
----------------
1. 20

Answer / t.lakshmi

count - It returns the non null values
count(*) - It returns the null values and duplicate values

Answer / vijay dev saxena

Count(expr) -> returns the number of records in the table
where the expr is not null in the particular column.
Count(*) -> returns the number of all records in the table.
(including duplicates and those with nulls)

Answer / sachin rathi

Count(column name or exp) returns the no. of records for a
specific/particular column of table excluding null values
whereas Count(*) returns all the rows/records in the table
including duplicated and null values

Answer / manisha

count fetches non-null value from out of a query but count
(*) includes null values also.

Answer / harish sharma

Count(column_name) returns the number of records in the
table where the column value is not null for the particular
column.
Count(*) returns the number of all records in the table.
(including duplicates and those with nulls)

Answer / rajeeva tripathi

count - It returns the non null values
count(*) - It returns the null values and duplicate values

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