Databases
StackOverflow2013
Postsdbo
POHow do I get the ID of a rows which have MAX and MIN values in SQL
 

Note that there are some explanatory texts on larger screens.

plurals
  1. POHow do I get the ID of a rows which have MAX and MIN values in SQL
    primarykey
    data
    text
    <p>I am trying to make the queries my website uses more efficient.</p> <p>Being a bit vague about SQL, I've not really learnt how to use nested queries, but I have just managed to get something that is pretty near what I want.</p> <p>I sell guitars, I have a big database with all the products with different finish options listed individually. Items have unique IDs in the dB but are grouped by their title, for example, a Gibson Les Paul Standard is listed in my dB 7 times with 7 different finish options. Not all the finish options will necessarily have the same price, and not all finish options will necessarily be in stock.</p> <p>In the search results page of my website I want to be able to show:</p> <p>1) Just one record per product, ie 1 record for Gibson LP Std, which can then be sub-linked to the different finishes.</p> <p>2) The actual product displayed must <em>either</em> be the cheapest finish option, OR, the cheapest in stock.</p> <p>This is currently working on my website, but it's using N+1 queries and seems to be running dreadfully slowly, but for an example of what I mean, click here: <a href="http://www.hartnollguitars.co.uk/search.asp?subcat=Gibson-Les-Pauls" rel="nofollow">http://www.hartnollguitars.co.uk/search.asp?subcat=Gibson-Les-Pauls</a> (if the bloody thing works)</p> <p>Part one is fine, I can just group the title in SQL, it's getting part 2 out that's the problem.</p> <p>Using the following SQL query I can get the lowest price and the highest price and I have counted how many variants there are, I also have the max and min stock levels.</p> <pre><code>results.Open "SELECT * FROM (SELECT *, count(id) as Variants, MAX(price) as highestPrice, MIN(price) as lowestPrice, MAX(shopstock) as highestStock, MIN(shopstock) as lowestStock FROM products WHERE item LIKE '%"&amp; replace([searchterm]," ","%") &amp;"%' GROUP BY item) AS UnknownVar LIMIT 40", conn, 3, &amp;H0001 </code></pre> <p>What I need to be able to do is get the ID value for the rows representing the max and min stock and price values.</p> <p>I basically need to be able to run if/or logic on it and I am not sure if this is possible.</p> <p>So, I need to be able to say </p> <pre><code>if Item_With_Cheapest_Price is in stock, display this as the thumbnail &amp; link else display first item in price sorted list where stock &gt;=1 </code></pre> <p>I also need a fall back, if none of the finishes are in stock, display the cheapest one.</p> <p>The database is MySQL using ODBC connections, I am currently scripting in Classic ASP but aim to upgrade to .NET, once I've worked out how!!! :-)</p>
    singulars
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PTQuestion
    1. USAdrian Carneiro
    1. USJamie Hartnoll
    plurals
    1. This table or related slice is empty.
    1. PL
      singulars
      1. LTLinked
    1. This table or related slice is empty.
    1. PO
      singulars
      1. PTAnswer
    2. PO
      singulars
      1. PTAnswer
    1. VO
      singulars
      1. POHow do I get the ID of a rows which have MAX and MIN values in SQL
      1. This table or related slice is empty.
      1. VTUpMod
    2. VO
      singulars
      1. POHow do I get the ID of a rows which have MAX and MIN values in SQL
      1. USJohn N
      1. VTFavorite
    3. VO
      singulars
      1. POHow do I get the ID of a rows which have MAX and MIN values in SQL
      1. USkralco626
      1. VTFavorite
    1. COto have an idea, how many records there are in the item table?
      singulars
      1. POHow do I get the ID of a rows which have MAX and MIN values in SQL
      1. USstivlo
    2. COstivlo; There are several thousand products in total, but the grouped value of item (ie Gibson Les Paul Standard) should have no more than about 20 finish options.
      singulars
      1. POHow do I get the ID of a rows which have MAX and MIN values in SQL
      1. USJamie Hartnoll
    3. COI was suspecting that. Unrelated to your question, but a reason for the slowness is this part of the query WHERE item LIKE '%"& replace([searchterm]," ","%" -- since the % sign is in front of the term indexes can't be used and MySQL will have to check **every single row**. Take a look at [full text search](http://dev.mysql.com/doc/refman/5.0/en/fulltext-search.html)
      singulars
      1. POHow do I get the ID of a rows which have MAX and MIN values in SQL
      1. USstivlo
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload