How to combine GROUP BY, ORDER BY and HAVING
How do I combine correctly this statement.
SELECT *, COUNT(*)
FROM user_log
GROUP BY Email
ORDER BY UpdateDate DESC
HA开发者_如何学PythonVING COUNT(*) > 1
Let me know
ORDER BY
is always last...
However, you need to pick the fields you ACTUALLY WANT then select only those and group by them. SELECT *
and GROUP BY Email
will give you RANDOM VALUES for all the fields but Email
. Most RDBMS will not even allow you to do this because of the issues it creates, but MySQL is the exception.
SELECT Email, COUNT(*)
FROM user_log
GROUP BY Email
HAVING COUNT(*) > 1
ORDER BY UpdateDate DESC
Steps for Using Group by,Having By and Order by...
Select Attitude ,count(*) from Person
group by person
HAving PersonAttitude='cool and friendly'
Order by PersonName.
Your code should be contain WHILE
before group by
and having
:
SELECT Email, COUNT(*)
FROM user_log
WHILE Email IS NOT NULL
GROUP BY Email
HAVING COUNT(*) > 1
ORDER BY UpdateDate DESC
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