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    <p>I would do almost an inverse of what Jasper provided... Start your query with your criteria to explicitly limit the few items that MAY qualify instead of getting all items and running a sub-select on each entry. Could pose as a larger performance hit... could be wrong, but here's my offering..</p> <pre><code>select i2.* from ( SELECT i.id FROM items i WHERE i.issue_date &gt; 2011 AND i.listed = 1 AND i.state_id = 5 GROUP BY i.id HAVING AVG( i.price) &lt;= 500 ) PreQualify JOIN items i2 on PreQualify.id = i2.id AND i2.issue_date &gt; 2011 AND i2.listed = 1 AND i2.state_id = 5 order by i2.price desc limit 25 </code></pre> <p>Not sure of the order by, especially if you wanted grouping by item... In addition, I would ensure an index on (state_id, Listed, id, issue_date)</p> <p>CLARIFICATION per comments</p> <p>I think I AM correct on it. Don't confuse "HAVING" clause with "WHERE". WHERE says DO or DONT include based on certain conditions. HAVING means after all the where clauses and grouping is done, the result set will "POTENTIALLY" accept the answer. THEN the HAVING is checked, and if IT STILL qualifies, includes in the result set, otherwise throws it out. Try the following from the INNER query alone... Do once WITHOUT the HAVING clause, then again WITH the HAVING clause...</p> <pre><code>SELECT i.id, avg( i.price ) FROM items i WHERE i.issue_date &gt; 2011 AND i.listed = 1 AND i.state_id = 5 GROUP BY i.id HAVING AVG( i.price) &lt;= 500 </code></pre> <p>As you get more into writing queries, try the parts individually to see what you are getting vs what you are thinking... You'll find how / why certain things work. In addition, you are now talking in your updated question about getting multiple IDs and prices at apparent low and high range... yet you are also applying a limit. If you had 20 items, and each had 10 qualifying records, your limit of 25 would show all of the first item and 5 into the second... which is NOT what I think you want... you may want 25 of each qualified "id". That would wrap this query into yet another level...</p>
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    1. POMySQL query for items where average price is less than X?
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    1. COLooks good, but I think it has a similar problem to Jasper's. The AVG(i.price) does not really get the AVG of the total set of items. If you group by state_id it's perhaps more appropriate, but it won't find you the X items that fall under AVG 500, it will basically just tell give you a positive result IF all items from state_id=5 have an AVG <= 500.
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    2. CO@Kaptron, Then remove the "State_ID" qualifier from the internal... Whatever your INTERNAL query to get the average basis IS will return whatever 1 ID you want. Then use THAT result to re-join out and put your other criteria the DOES include your State_ID element.
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    3. COPerhaps I'm still not being entirely clear.Tudor's answer seemed to understand the problem. Essentially I'm trying to do a query where the total items *average* out to <= 500, meaning it could include items of prices 490, 500, and 510. The queries I've seen here only will include items that individually have prices <=500 rather than averaging out to 500 over the whole set.
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