Select limit question

[Shane Wegner]

Hi,

I am trying to write a routine to calculate an average based on the 5
entries before a certain entry in a table based on the _date column.

Is this possible with a select statement?  The limit keyword has an offset
and a limit but can you tell select to return the 5 entries before a
certain entry.

Example:
create table chart(
_date date,
symbol varchar(10),
close double(22,3),
5avg double(22,3);

5avg should be the last 5 closing values for a symbol.  Any ideas on how
to do this most efficiently with MySQL would be greatly appreciated.
Please cc me on replies.

Thanks in advance,
Shane

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Shane Wegner: shane@stripped
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