Counting Students1:01 with Ben Deitch
How many students do they have at Jefferson Middle School?
Not bad. 0:00 How about this? 0:01 How many total students are at the school? 0:02 For this report, we'll need to be using the students table, 0:06 and we'll need to be selecting a count of all the students. 0:08 And to do that, we'll type SELECT, then COUNT, and 0:13 usually you'll COUNT(*), and then FROM STUDENTS. 0:17 Then we can run the query and we have 512 students. 0:23 Another interesting thing to mention is this star here. 0:26 When you're doing a count over a table, it's perfectly fine to count everything, 0:30 but it's also perfectly fine to just count 1. 0:35 And so, if we use Shift+Enter here, we get the same answer. 0:38 Now using 1 or * doesn't really make any difference, 0:42 just know that you can use either or. 0:45 You could even use a 10, or even a column name. 0:48 So STUDENTS.FIRST_NAME and we'll always get the same count. 0:53
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