I have a table with the following columns
id => int not null auto_increment
stockid => integer
tdate => date
price => float
primary key (id)
key (productid)
The table has 8,000,000+ rows holding 8000+ different stockids.
I have to pull various information from the table the first query is to get
the average
price for the last 10 days.
select avg(price) from table1 where tdate>date_sub(today, interval 10 day)
1. How can I optimize this query?
2. Are there any advantages to using an index on the tdate column?
Secondly, I need to get all stockids which have today's price greater than
yesterday's.
Here is how I do this now I am looking for a single statement if
possible.
select price where tdate=yesterday and stockid=xxx
select price where tdate=today and stockid=xxx
compare selected values
1. Is this possible with one select?
2. Best way to optimize the table for quickest access to the data?
Thanks in advance.
Edward
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