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How many students do they have at Jefferson Middle School?
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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,
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but it's also perfectly
fine to just count 1.
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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,
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just know that you can use either or.
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You could even use a 10,
or even a column name.
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So STUDENTS.FIRST_NAME and
we'll always get the same count.
0:53
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