So, I figure I could probably come up with some wacky solution, but i figure i might as well ask up front.
each user can have many orders.
each desk can have many orders.
each order has maximum 3 items in it.
trying to set things up so a user can create an order and the order auto generates a reference number and each item has a reference letter. reference number is 0-99 and loops back around to 0 once it hits 99, so orders throughout the day are easy to reference for the desks.
So, user places an order for desk #2 of 3 items:
78A: red stapler
78B: pencils
78C: a kangaroo foot
not sure if this would be done in the program logic or done at the SQL level somehow.
was thinking something like neworder = order.last + 1 and somehow tying that into a range on order create. pretty fuzzy on specifics.
Without knowing the answer to my comment above, I will assume you want to have the full audit stored, rather than wiping historic records; as such the 78A 78B 78C type orders are just a display format.
If you have a single Order table (containing your OrderId, UserId, DeskId, times and any other top-level stuff) and an OrderItem table (containing your OrderItemId, OrderId, LineItemId -- showing 1,2 or 3 for your first and optional second and third line items in the order, and ProductId) and a Product table (ProductId, Name, Description)
then this is quite simple (thankfully) using the modulo operator, which gives the remainder of a division, allowing you in this case to count in groups of 3 and 100 (or any other number you wish).
Just do something like the following:
(you will want to join the items into a single column, I have just kept them distinct so that you can see how they work)
Obviously join/query/filter on user, desk and product tables as appropriate
select
o.OrderId,
o.UserId,
o.DeskId
o.OrderId%100 + 1 as OrderNumber,
case when LineItem%3 = 1 then 'A'
when LineItem%3 = 2 then 'B'
when LineItem%3 = 0 then 'C'
end as ItemLetter,
oi.ProductId
from tb_Order o inner join tb_OrderItem oi on o.OrderId=oi.OrderId
Alternatively, you can add the itemLetter (A,B,C) and/or the OrderNumber (1-100) as computed (and persisted) columns on the tables themselves, so that they are calculated once when inserted, rather than recalculating/formatting when they are selected.
This sort-of breaks some best practice that you store the raw data in the DB and you format on retrieval; but if you are not going to update the data and you are going to select the data for more than you are going to write the data; then I would break this rule and calculate your formatting at insert time
Related
I have a database in which there are 13 different products, sold in 6 different countries.
Prices increase once a year.
Prices need to be calculated using a linear interpolation method. I have 21 different price and quantity increments for each product for each country for each year.
The user needs to be able to see how much an order would cost for any given value (as you would expect).
What the database needs to do (in English!) is to:
If there is a matching quantity from TblOrderDetail in the TblPrices,
use the price for the current product, country and year
if there isn't a matching quantity but the quantity required is greater than 1000 for one product (GT) and greater than 100 for every other product:
Find the highest quantity for the product, country and year (so, 1000 or 100, depending on the product), and calculate a pro-rated price. eg. If someone wanted 1500 of product GT for the UK for 2015, we'd look at the price for 1000 GT in the UK for 2015 and multiply it by 1.5. If 1800 were required, we'd multiply it by 1.8. I haven't been able to get this working yet as I'm looking at it alongside the formula for the next possibility...
If there isn't a matching quantity and the quantity required is less than 1000 for the product GT but 100 for the other products (this is the norm)...
Find the quantity and price for the increment directly below the quantity required by the user for the required product, country and year (let's call these quantitybelow and pricebelow)
Find the quantity and price for the increment directly above the quantity required by the user for the required product, country and year (let's call these quantityabove and priceabove)
Calculate the price for the required number of products for an account holder in a particular country for a given year using this formula.
ActualPrice: PriceBelow + ((PriceAbove - PriceBelow) * (The quantity required in the order detail - QuantityBelow) / (QuantityAbove - QuantityBelow))
I have spent days on this and have sought advice about this before but I am still getting very stuck.
The tables I've been working with to try and make this work are as follows:
TblAccount (primary key is AccountID, it also has a Country field which joins to the TblCountry.Code (primary key)
TblOrders (primary key is Order ID) which joins to TblAccount via the AccountID field; TblOrderDetail via the OrderID. This table also holds the OrderDate and Recipient ID which links to a person in TblContact - I don't need that here but will need it later to generate an invoice
TblOrderDetail (primary key is DetailID) which joins to TblOrders via OrderID field; TblProducts via ProductID field, and holds the Quantity required as well as the product
TblProducts (primary key is ProductCode) which as well as joining to TblOrderDetail, also joins to TblPrice via the Product field
TblPrices links to the TblProducts (as you have just read). I've also created an Alias for the TblCountry (CountryAliasForProductCode) so I can link it to the TblPrices to show the country link. I'm not sure if I needed to do this - it doesn't work if I do or I don't do it, so I seek guidance again here.
This is the code I've been trying to use (and failing) to get my price and quantity steps above and I hope to replicate it, making a couple of tweaks to get the steps below:
SELECT MIN(TblPrices.stepquantity) AS QuantityAbove, MIN(TblPrices.StepPrice) AS PriceAbove, TblOrders.OrderID, TblOrders.OldOrderID, TblOrders.AccountID, TblOrders.OrderDate, TblOrders.RecipientID, TblOrders.OrderStatus, TblOrderDetail.DetailID, TblOrderDetail.Product, TblOrderDetail.Quantity
FROM (TblCountry INNER JOIN ((TblAccount INNER JOIN TblOrders ON TblAccount.AccountID = TblOrders.AccountID) INNER JOIN (TblOrderDetail INNER JOIN TblProducts ON TblOrderDetail.Product = TblProducts.ProductCode) ON TblOrders.OrderID = TblOrderDetail.OrderID) ON TblCountry.Code = TblAccount.Country) INNER JOIN (TblCountry AS CountryAliasForProduct INNER JOIN TblPrices ON CountryAliasForProduct.Code = TblPrices.CountryCode) ON TblProducts.ProductCode = TblPrices.Product
WHERE (StepQuantity >= TblOrderDetails.Quantity)
AND (TblPrices.CountryCode = TblAccount.Country)
AND (TblOrderDetail.Product = TblPrices.Product)
AND (DATEPART('yyyy', TblPrices.DateEffective) = DATEPART('yyyy', TblOrders.OrderDate));
I've also tried...
I've even tried going back to basics and trying again to generate the steps below in 1 query, then try the steps above in another and finally, create the final calculation in another query.
This is what I have been trying to get my prices and quantities below:
SELECT Max(StepQuantity) AS quantity_below, Max(StepPrice) AS price_below, TblOrderDetails.Quantity, TblAccounts.Country
FROM
(TblProducts INNER JOIN TblPrices ON TblProducts.ProductCode = TblPrices.Product)
(TblOrderDetail INNER JOIN TblProducts ON TblOrderDetail.Product = TblProducts.ProductCode)
(TblOrders INNER JOIN TblOrderDetail ON TblOrders.OrderID = TblOrderDetail.OrderID)
(TblAccount INNER JOIN TblOrders ON TblAccount.AccountID = TblOrders.AccountID),
WHERE (((TblPrices.StepQuantity)<=(TblOrderDetail.Quantity)) AND ((TblPrices.CountryCode)=([TblAccounts].[country])) AND ((TblPrices.Product)=([TblOrderDetail].[product])) AND ((DatePart('yyyy',[TblPrices].[DateApplicable]))=(DatePart('yyyy',[TblOrders].[OrderDate]))));
You may be able to see glaring errors in this but I'm afraid I can't. I've tried re-jigging it and I'm getting nowhere.
I need to be able to tie the information in to the OrderDetail records as the price generated will need to be added to a financial transactions table as a debit amount and will show as an amount owing on statements.
I'm really not very good at SQL. I've read and worked though several self-study books and I have asked part of this question before; but I really am struggling with it. If anyone has any ideas on how to proceed, or even where I've gone wrong with my code, I'd be delighted, even if you tell me I shouldn't be using SQL. For the record, I originally posted this question on a different forum under Visual Basic. Responses from that forum brought me to SQL - however, anything that works would be good!
I've even tried, using Excel, concatenating the Year&Product&Country&Quantity to get a unique product code, interpolating the prices for every quantity between 1 and 1000 for each product, country and year and bringing them into a TblProductsAndPrices table. In Access, I created a query to concatenate the Year(of order date from tblOrders)&Product(of tblorderdetails)&Country(of tblAccount) in order to get the required product code for the order. Another query would find a price for me. However, any product code that doesn't appear on the list (such as where a quantity isn't listed in the tblProductsAndPrices as it is larger than the highest price increment) doesn't have a price.
If there was a workable solution to what I've just described that would generate a price for everything, then I'd be so pleased.
I'd really like to be able to generate an order for any quantity of any product for any account based in any country on any date and retrieve a price which will be used to "debit" a financial account in the database, who in a transaction history for an account and appear on statements. I'd also like to be able to do an ad-hoc price check on the spot.
Thank you very much for taking the time to read this. I really appreciate it. If you could offer any help or words of encouragement, I'd be very grateful.
Many thanks
Karen
Maybe no one thinks on an easy solution to the problem, since not all minds work in database thinking.
Easy solution: Create one view that gives all calculated values, not only the final one you need, each one as a column. Then you can use such view in a relation view and use on some rows one of the values and on other rows other values, etc.
How to think is simple, think in reverse order, instead of thinking "if that then I need to calculate such else I need this other", think as "I need "such" and I need "this other", both are columns of an intermediate view, then think on top level "if" that would be another view, such view will select the correct value ignoring the rest.
Never ever try to solve all in one step, that can be a really big headache.
Pros: You can isolate calculated values (needed or not), sql is much more easy to write and maintain.
Cons: Resources use is bigger than minimal, but most of times that extra calculated values does not represent a really big impact.
In terms of tutorial out there: Instead of a Top-Down method, use a Down-Top method.
Sometimes it is better (with your example) to calculate all three values (you write sentences on bold) ignoring the if part, and have all three possible values for your order and after that discard the ones not wanted, than trying to only calculate one.
Trying to calculate only one is thinking as a procedural programming, when working with databases most times one must get rid of such thinking and think as reverse, first do the most internal part of such procedural programming to have all data collected, then do the external selection of the procedural programing.
Note: If one of the values can not be calculated, just generate a Null.
I know it is hard to think on First in, last out (Down-Top) model, but it is great for things as the one you want.
Step1 (on specific view, or a join from one view per calculation):
Calculate column 1 as price for the current product, country and
year
Calculate column 2 as calculate a pro-rated price as if 1000
Calculate column 3 as calculate a pro-rated price as if 100
Calculate column 4 as etc
Calculate column N as etc
Step 2 (Another view, the one you want):
Calculate the if part, so you can choose adequate column from previous view (you can use immediately if or a calculated auxiliary field).
Hope you can follow theese way of thinking, I have solved a lot of things like that one (and more complex) thinking in that way, but it is not easy to think as that, needs an extra effort.
I am discovering SQL as I have to build queries in my new company.I have understood the basic but here is where I am stuck, maybe you could help me figure this out :
I would like to mention a product as unprocurable if sellers rejected my orders twice. Tricky part I aggregate the furniture orders for all our local offices, therefore even though I sent my purchase order(s) to one unique seller (the one with the best offer at the moment) I might have multiple lines for each item (one per office)
See below table for purchase orders, see REF1 item should be set as unprocurable as both on 21 and 31 december my orders have been rejected (no matter the seller)
http://i.stack.imgur.com/r3W3E.jpg
So to put it in logic I would like to have something like this:
For each items with 2 latest purchase orders that were both made at different dates and rejected(0 value in the table) THEN attach a note to it saying "unprocurable" else put as procurable.
IF it was only 1 value I think I could go with
Select
item
, MAX(date)
, case
when confirmed_units = 0
then 'Unprocurable'
else 'procurable'
end
From
purchase_table
Where
date between TO_DATE('01/01/2013', 'MM/DD/YYYY') AND TO_DATE('{RUN_DATE_YYYY/MM/DD}', 'YYYY/MM/DD')
But now I need to check the two latest purchase orders and that are not from the same day.
I am a bit lost, could you give a hand please?
Thanks !
Your question is a little unclear... have you tried using something along the lines of:
SELECT TOP 2 etc, etc... order by [column]
I have a table that lists thousands of products. A product can be either Standard (123450.000.000), one colour (123456.BLA.000), one size (123456.000.LAR) or both colour and size (123456.BLA.LAR).
A product can have multiple colours (123456.BLA.000, 123456.YEL.OOO etc etc). I am trying to do a query that brings back a product that has multiple colours but only one colour in stock i.e. ProductQTY = 1 and the remaining colours are out of stock.
All I have been able to come up with is the query below but this just brings back all 'variant' products that have 1 in stock. What do I have to add or change to make it bring back results whereby a product has different colours but only ONE of those colours are in stock and the remaining are out of stock? Do I need to do a UNION?
select *
from Product
where productcode NOT LIKE ('%000.000')
AND ProductQTY = '1'
First off, that's a terrible structure. Store color and size information in separate tables, don't make them part of one massive variable.
Second, you want to do a query that selects Product IDs (1-6, looks like) that have a count > 1 with color present and the sum of their quantities is 1 exactly (according to your question - if that one record could have a qty>1 and still be okay, this is a little more complicated).
select * from product where substr(product,1,6) in (
select substr(product,1,6) from product
where not (product like '%.000.%')
group by 1
having count(1) > 1
and sum(ProductQTY)=1
)
The question would be much easier if you would split up the properties in different columns. But you could do that in a query aswell:
select code from
(select substring(productcode,-3) as size,
substring(productcode,-7,3) as colour,
substring(productcode,0,len(prodcutcode)-7) as code
from product) t
group by code
having sum(productQTY) = 1
//or count(*) = 1 to get all unique ones
Imagine an auction (ebay auction, for example). You create an auction, set the start bidding value, let's say, 5 dollars. This gets stored as a minimal bid value to the auctions table.At this point, the current bid value of this auction is 5 dollars.
Now, if someone bids to your auction, let's say, 10 dollars, this gets stored to the bids table.At this point, the current bid value of this auction is 10 dollars.
Now let's imagine you want to retrieve 5 cheapest auctions. You will write a query like this:
SELECT
`auction_id`,
`auction_startPrice`,
MAX(bids.bid_price) as `bid_price`
FROM
`auctions`
LEFT JOIN `bids` ON `auctions`.`auction_id`=`bids`.`bid_belongs_to_auction`
GROUP BY `auction_id`
LIMIT 5
Pretty simple, and it works! But now you need to add an ORDER BY clause to the query. The problem is, however, that we want to ORDER BY either by auctions.auction_startPrice or by bid_price, depending on whichever of this is higher, as explained in the first paragraphs.
Can this be understood? I know how to do this using 2 queries, but I am hoping it can be done with 1 query.
Thanks!
EDIT: Just a further explanation to help you imagine the problem. If I set ORDER BY auction_startPrice ASC, then I will get 5 auctions with their lowest initial bid price, but what if there are already bids placed on those auctions? Then their current lowest price is equal to those bids, NOT to the start price, therefore my query is wrong.
SELECT
`auction_id`,
`auction_startPrice`,
`bid_price`
FROM
(
SELECT
`auction_id`,
`auction_startPrice`,
MAX(bids.bid_price) as `bid_price`,
IF(MAX(bids.bid_price)>`auction_startPrice`,
MAX(bids.bid_price),
`auction_startPrice`) higherPrice
FROM
`auctions`
LEFT JOIN `bids` ON `auctions`.`auction_id`=`bids`.`bid_belongs_to_auction`
GROUP BY `auction_id`
) X
order by higherPrice desc
LIMIT 5;
Note:
In the inner query, an extra column is created, named 'higherPrice'
The IF function compares the MAX(bid_price) column against the startprice, and only if the Max-bid is not null (implicitly required in comparison) and greater than start price, then the Max-bid becomes the value in the higherPrice column. Otherwise, it will contain the start price.
The outer query merely makes use of the columns from the inner query, ordering by the higherPrice
I'm not sure which database you're using but look at this example:
http://www.extremeexperts.com/sql/articles/CASEinORDER.aspx
SELECT
`auction_id`,
`auction_startPrice`,
MAX(bids.bid_price) as `bid_price`
FROM
`auctions`
LEFT JOIN `bids` ON `auctions`.`auction_id`=`bids`.`bid_belongs_to_auction`
GROUP BY `auction_id`
ORDER BY CASE WHEN `auction_startPrice` > isnull(MAX(bids.bid_price),0) then `auction_startPrice` else MAX(bids.bid_price) end
LIMIT 5
It would seem that there is a much simpler way to state the problem. Please see Edit 2, following the sample table.
I have a number of different products on a production line. I have the date that each product entered production. Each product has two identifiers: item number and serial number I have the total number of labour hours for each product by item number and by serial number (i.e. I can tell you how many hours went into each object that was manufactured and what the average build time is for each kind of object).
I want to determine how (if) varying the length of production runs affects the average time it takes to build a product (item number). A production run is the sequential production of multiple serial numbers for a single item number. We have historical records going back several years with production runs varying in length from 1 to 30.
I think to achieve this, I need to be able to assign 'run id'. To me, that means building a query that sorts by start date and calculates a new unique value at each change in item number. If I knew how to do that, I could solve the rest of the problem on my own.
So that suggests a series of related questions:
Am I thinking about this the right way?
If I am on the right track, how do I generate those run id values? Calculate and store is an option, although I have a (misguided?) preference for direct queries. I know exactly how I would generate the run numbers in Excel, but I have a (misguided?) preference to do this in the database.
If I'm not on the right track, where might I find that track? :)
Edit:
Table structure (simplified) with sample data:
AutoID Item Serial StartDate Hours RunID (proposed calculation)
1 Legend 1234 2010-06-06 10 1
3 Legend 1235 2010-06-07 9 1
2 Legend 1237 2010-06-08 8 1
4 Apex 1236 2010-06-09 12 2
5 Apex 1240 2010-06-10 11 2
6 Legend 1239 2010-06-11 10 3
7 Legend 1238 2010-06-12 8 3
I have shown that start date, serial, and autoID are mutually unrelated. I have shown the expectation that labour goes down as the run length increases (but this is a 'fact' only via received wisdom, not data analysis). I have shown what I envision as the heart of the solution, that being a RunID that reflects sequential builds of a single item. I know that if I could get that runID, I could group by run to get counts, averages, totals, max, min, etc. In addition, I could do something like hours/ to get percentage change from the start of the run. At that point I could graph the trends associated with different run lengths either globally across all items or on a per item basis. (At least I think I could do all that. I might have to muck about a bit, but I think I could get it done.)
Edit 2: This problem would appear to be: how do I get the 'starting' member (earliest start date) of each run when I don't already have a runID? (The runID shown in the sample table does not exist and I was originally suggesting that being able to calculate runID was a potentially viable solution.)
AutoID Item
1 Legend
4 Apex
6 Legend
I'm assuming that having learned how to find the first member of each run that I would then be able to use what I've learned to find the last member of each run and then use those two results to get all other members of each run.
Edit 3: my version of a query that uses the AutoID of the first item in a run as the RunID for all units in a run. This was built entirely from samples and direction provided by Simon, who has the accepted answer. Using this as the basis for grouping by run, I can produce a variety of run statistics.
SELECT first_product_of_run.AutoID AS runID, run_sibling.AutoID AS itemID, run_sibling.Item, run_sibling.Serial, run_sibling.StartDate, run_sibling.Hours
FROM (SELECT first_of_run.AutoID, first_of_run.Item, first_of_run.Serial, first_of_run.StartDate, first_of_run.Hours
FROM dbo.production AS first_of_run LEFT OUTER JOIN
dbo.production AS earlier_in_run ON first_of_run.AutoID - 1 = earlier_in_run.AutoID AND
first_of_run.Item = earlier_in_run.Item
WHERE (earlier_in_run.AutoID IS NULL)) AS first_product_of_run LEFT OUTER JOIN
dbo.production AS run_sibling ON first_product_of_run.Item = run_sibling.Item AND first_product_of_run.AutoID run_sibling.AutoID AND
first_product_of_run.StartDate product_between.Item AND
first_product_of_run.StartDate
Could you describe your table structure some more? If the "date that each product entered production" is a full time stamp, or if there is a sequential identifier across products, you can write queries to identify the first and last products of a run. From that, you can assign IDs to or calculate the length of the runs.
Edit:
Once you've identified 1,4, and 6 as the start of a run, you can use this query to find the other IDs in the run:
select first_product_of_run.AutoID, run_sibling.AutoID
from first_product_of_run
left join production run_sibling on first_product_of_run.Item = run_sibling.Item
and first_product_of_run.AutoID <> run_sibling.AutoID
and first_product_of_run.StartDate < run_sibling.StartDate
left join production product_between on first_product_of_run.Item <> product_between.Item
and first_product_of_run.StartDate < product_between.StartDate
and product_between.StartDate < run_sibling.StartDate
where product_between.AutoID is null
first_product_of_run can be a temp table, table variable, or sub-query that you used to find the start of a run. The key is the where product_between.AutoID is null. That restricts the results to only pairs where no different items were produced between them.
Edit 2, here's how to get the first of each run:
select first_of_run.AutoID
from
(
select product.AutoID, product.Item, MAX(previous_product.StartDate) as PreviousDate
from production product
left join production previous_product on product.AutoID <> previous_product.AutoID
and product.StartDate > previous_product.StartDate
group by product.AutoID, product.Item
) first_of_run
left join production earlier_in_run
on first_of_run.PreviousDate = earlier_in_run.StartDate
and first_of_run.Item = earlier_in_run.Item
where earlier_in_run.AutoID is null
It's not pretty, and will break if StartDate is not unique. The query could be simplified by adding a sequential and unique identifier with no gaps. In fact, that step will probably be necessary if StartDate is not unique. Here's how it would look:
select first_of_run.AutoID
from production first_of_run
left join production earlier_in_run
on (first_of_run.Sequence - 1) = earlier_in_run.Sequence
and first_of_run.Item = earlier_in_run.Item
where earlier_in_run.AutoID is null
Using outer joins to find where things aren't still twists my brain, but it's a very powerful technique.