In this example, we have a table for young campers with the columns of id, name, age and counselor. The computer will ignore any duplicate values. The DISTINCT keyword will only count unique values that are NOT NULL. SELECT COUNT(DISTINCT column_name) FROM table_name Sometimes you will see the DISTINCT keyword used with the COUNT function. You can omit this keyword because the COUNT function uses the ALL keyword as the default whether you write it or not. The ALL keyword will count all values in the table including duplicates. SELECT COUNT(ALL column_name) FROM table_name You can also use the ALL keyword in the COUNT function. The FROM clause in SQL specifies which table we want to list. The COUNT(*) function will return the total number of items in that group including NULL values. Sometimes you can use an * inside the parenthesis for the COUNT function. The SELECT statement in SQL tells the computer to get data from the table.ĬOUNT(column_name) will not include NULL values as part of the count.Ī NULL value in SQL is referring to values that are not present in the table. Here is the basic syntax: SELECT COUNT(column_name) FROM table_name This SQL function will return the count for the number of rows for a given group. In this article, I will show you how to use the COUNT function with a few code examples. In SQL, you can make a database query and use the COUNT function to get the number of rows for a particular group in the table.
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