Order statistic in MySQL

Hello, all!

I am currently keeping my student's grades in MS Excel, but I am
considering migrating to MySQL. The only problem is this: I need to drop
the *two* lowest quiz grades in computing the final grade.

Is there a way to do this in MySQL? I know how to get the *lowest* quiz
grade, but how do I compute the *two* lowset quiz grades?

Thanks in advance for any assistance you can provide.

Sincerley,
--
Jeffrey Rolland | "Beneath this mask there is more than
<wildstar200@hotmail.com> | flesh. There is an idea, Mr. Creedy, and
| ideas are bulletproof. "
| - _V for Vendetta_

In article
<wildstar200-4457A4.11522522042006@216-165-192-90.crescentb.com>,
Jeffrey Rolland <wildstar200@hotmail.com> wrote:

> Hello, all!
>
> I am currently keeping my student's grades in MS Excel, but I am
> considering migrating to MySQL. The only problem is this: I need to drop
> the *two* lowest quiz grades in computing the final grade.
>
> Is there a way to do this in MySQL? I know how to get the *lowest* quiz
> grade, but how do I compute the *two* lowset quiz grades?
>
> Thanks in advance for any assistance you can provide.
>
> Sincerley,


Ted wrote:
> If you REALLY want the two lowest grades (or more precisely the records
> containingthe two lowest grades), you'd use ORDER BY combined with
> LIMIT 2 in a SELECT statement.
>
> I suspect what you really want is to select all grades except the two
> lowest grades.
>
> If you know the number of grades, you'd use an ORDER BY, along with
> DESC (so you're sorting in descending order), combined with a LIMIT
> with a number two less than the number of grades. If the number of
> grades is unknown, or can vary, then you have a little extra
> complexity, because you'd need to use count() to get the number of
> grades before selecting all grades except the two lowest grades.
>
> You can look up the exact syntax in the MySQLmanual.
>
> I hope this helps.
>
> Ted

I want all grades except the last two.

Just to be clear, I want to get all grades except for the last two *for*
*each* *record*. I think that LIMIT limits the number of records, not
the number of grade fields in each record. It LIMIT does limit the
number of grade fields, that would do it.

I have PHP installed on my system, so a PHP/MySQL solution would also
work (to relpy to another poster).

Thanks for your replies. This is a crosspost to alt.comp.databases.mysql

Sincerley,
--
Jeffrey Rolland | "Beneath this mask there is more than
<wildstar200@hotmail.com> | flesh. There is an idea, Mr. Creedy, and
| ideas are bulletproof. "
| - _V for Vendetta_

Jeffrey Rolland wrote:
> In article
> <wildstar200-4457A4.11522522042006@216-165-192-90.crescentb.com>,
> Jeffrey Rolland <wildstar200@hotmail.com> wrote:
>
>
>>Hello, all!
>>
>>I am currently keeping my student's grades in MS Excel, but I am
>>considering migrating to MySQL. The only problem is this: I need to drop
>>the *two* lowest quiz grades in computing the final grade.
>>
>>Is there a way to do this in MySQL? I know how to get the *lowest* quiz
>>grade, but how do I compute the *two* lowset quiz grades?
>>
>>Thanks in advance for any assistance you can provide.
>>
>>Sincerley,
>
>
>
> Ted wrote:
>
>>If you REALLY want the two lowest grades (or more precisely the records
>>containingthe two lowest grades), you'd use ORDER BY combined with
>>LIMIT 2 in a SELECT statement.
>>
>>I suspect what you really want is to select all grades except the two
>>lowest grades.
>>
>>If you know the number of grades, you'd use an ORDER BY, along with
>>DESC (so you're sorting in descending order), combined with a LIMIT
>>with a number two less than the number of grades. If the number of
>>grades is unknown, or can vary, then you have a little extra
>>complexity, because you'd need to use count() to get the number of
>>grades before selecting all grades except the two lowest grades.
>>
>>You can look up the exact syntax in the MySQLmanual.
>>
>>I hope this helps.
>>
>>Ted
>
>
> I want all grades except the last two.
>
> Just to be clear, I want to get all grades except for the last two *for*
> *each* *record*. I think that LIMIT limits the number of records, not
> the number of grade fields in each record. It LIMIT does limit the
> number of grade fields, that would do it.
>
> I have PHP installed on my system, so a PHP/MySQL solution would also
> work (to relpy to another poster).
>
> Thanks for your replies. This is a crosspost to alt.comp.databases.mysql
>
> Sincerley,

Ok, you know the number of records (or you can get them with count). Just order
by grade descending and limit to the number of records less 2.



--
==================
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Jerry Stuckle
JDS Computer Training Corp.
jstucklex@attglobal.net
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