Sign Up to our social questions and Answers Engine to ask questions, answer people’s questions, and connect with other people.
Login to our social questions & Answers Engine to ask questions answer people’s questions & connect with other people.
Lost your password? Please enter your email address. You will receive a link and will create a new password via email.
Please briefly explain why you feel this question should be reported.
Please briefly explain why you feel this answer should be reported.
Please briefly explain why you feel this user should be reported.
SELECT COUNT(1) FROM STUDENTS
SELECT COUNT(*) FROM STUDENTS
Both the queries return the same result, but is there any performance difference between these two ?
What I had heard is the first query would be faster than the second one, but can any one give specific details about it?
You may use
count(*)orcount(1), one is not faster than the other. As stated, is just a urban legend 🙂One final note,
count(*)andcount(columnName)may be different!The first one counts all rows, the second one counts the number of rows where the specified column is not NULL.