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what is the difference between count(*) and count(1)

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count(*) it will count the number of records for each fields/columns and count(1) it will count the number of records for the first field... Answered By: SAM    Date: 7/24/2007 there is no differnce thats give same outputs Answered By: heman    Date: 7/28/2007 Count(*) will count all the no of records in the table irrespective of the fields whether they or null or not when we select. where as count(1) will not consider the null records Answered By: RR    Date: 8/1/2007 Count(*) will return the no of rows present in the table including the null values bun in case of count() will return non null records i.e it will not displayed the null values present in the record Answered By: neelamadhab padhy    Date: 8/20/2007 count(*) and count(1) will count the number of records in all the fields and in the first field respectively Answered By: puneet    Date: 8/26/2007 Count(*) will return the no of rows present in the table including the null values bun in case of count() will return non null records i.e it will not displayed the null values present in the record Answered By: sudhan    Date: 10/22/2007 No difference both we give the same output Answered By: vidhya    Date: 11/21/2007 Count(1) is faster to count(*). Answered By: V.Karthikeyan    Date: 1/1/2008 Count(1) is faster to count(*). Answered By: V.Karthikeyan    Date: 1/1/2008 both gives the same output ..... Answered By: Abhishek Verma    Date: 1/2/2008 There is difference, Count(*) is slower than count(1) query. using Count(1) improves performance and its substantial in case of tables > 20K rows Answered By: sagar    Date: 2/5/2008 count(*) will return the all the rows in a table,count(1) is only one row record is appear. Answered By: venkat    Date: 2/6/2008 Both Will give same results Answered By: Sharanabasappa    Date: 2/6/2008 In most Cases the first feild will be primary key and we will get same number as output... Answered By: pax    Date: 2/6/2008 count(*)will be count the no of records in field and count(1)will be count the only one record field Answered By: surendra    Date: 2/11/2008 count(*) will count all fields in record count(1) counts only first field of the record Answered By: Jhansi    Date: 2/12/2008 Both will give the same output, the difference is count(1) is faster compared to count(*) Answered By: Jyothi    Date: 3/4/2008 No difference between count(*) and count(1) but if you write count(empname) (or any field name) it will count all rows which donot have any null value,i.e it does not count null values rows. Answered By: Rajesh    Date: 3/5/2008 Count(*) will count the number of records and it also count the number of records for particular field....but the count(1) count the number of records only. Answered By: R.Pradeep    Date: 3/19/2008 Count(*) will give gives count of NULL where as count(1) gives record in that column. Answered By: MD    Date: 3/31/2008 count(1) is faster to count(*). on difference answer both we give the same output. Answered By: shailendra singh    Date: 4/1/2008 count(*) returns number of records in a relation including null values. and count() returns number of records in a relation except null values. Answered By: Tanveer    Date: 5/8/2008 count(1) will consider the nulls and is same as count(*) except it gives the count of the first column. Count(col_name) will not count the nulls. It returns only non-null record count. Answered By: gsr    Date: 5/12/2008 count(*) will include all values including null values but count(1) give output excluding null values Answered By: amit     Date: 5/28/2008 Count(*) will return the no of rows present in the table including the null values but in case of count(1) will return non null records . Answered By: surya mani singh    Date: 6/8/2008 Both will give the same output, the difference is count(1) is faster compared to count(*) . Answered By: Sampath Kumar    Date: 7/1/2008 Count(*) will return the no of rows present in the table including the null values, but in case of count(1) will return non null records. Answered By: sampath    Date: 7/1/2008 Count(1) refers rowid directly Count(col name) refers column name and nulls are not considered Count(*) refers all the columns irrespsctive of nulls present. Ultimately count(1) is always faster. Answered By: Antony Raj    Date: 7/15/2008 The difference is count(1) is faster than count(*). Answered By: sandeep    Date: 8/7/2008 © NewInterviewQuestions.com

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