I am trying to determine medicare costs per capita in each State using Google BigQuery.
I already have population numbers for each state (represented as Total) as well as total medicare cost (Cost) in each state. I am trying to divide total cost by the population of each state.
At the moment the query runs, however every entry is null. I am admittedly a beginner with both BigQuery and SQL.
Here is my code:
SELECT State, Cost / Total AS PerCapita
FROM medicare.population, medicare.CostByState
GROUP BY State, PerCapita;
One thing that may be causing issues is that the 'State' column exists in both 'population' and 'CostByState' tables. Not sure how to address this.
Here are my tables:
population
CostByState
You seem to have data with one row per state, so you only need a JOIN.
SELECT p.State, cbs.Cost / p.Total AS PerCapita
FROM medicare.population p JOIN
medicare.CostByState cbs
ON p.state = cbs.state;
You would only need aggregation if the tables had multiple rows per state.
Indeed you need to join that.
If the relationship is one to one you're good. But if not you may need some type of aggregation
sum(cost)/sum(total) as per_capita
Related
so i have a question regarding Average problem. suppose i have 5 transactions, with each transaction having multiple items and each item has their own Quantity Value. I want to search Average Quantity per transaction. Note that in my ERD Design, there are 2 separate tables which are HeaderTransaction and TransactionDetail.
If i use AVG() function, then it will be very weird as i.e.
first transaction:
5 eggs
2 sausages
Second transaction :
3 eggs
10 sausages.
AVG will work like (5+2+3+10)/4 what i want is ((5+2)+(3+10))/2
my current solution is
SELECT SUM(ItemQuantity)/COUNT (DISTINCT (SalesTransactionId)) as[aveg]
i find it a bit rough
If i use AVG() function, then it will be very weird
Not if you AVG what you say you want to average, which is the number of items per transaction
SELECT AVG(num_of_items_in_transaction)
FROM
(SELECT SUM(amount_of_item) as num_of_items_in_transaction FROM detail GROUP BY tran_id)
The inner query groups per transaction, and counts the total number of items. The outer query then averages these totals. The point is that because you need to first do an operation group by transaction, then another operation group by something else (the whole dataset) you can't combine the grouping operations into a single step - it has to be multi stage, because you're feeding the output from one stage into the input of another. SELECT AVG(SUM(amount)) .. GROUP BY ??? - what would you put into the ??? to let MySQL know you wanted the SUM grouping by one thing but the AVG grouping by another? (You can't)
You generally need to do it as a two step reduction if you're not windowing, but that's conceivably a implicit multi-step operation anyway
I don't think there's any need to change what you have (sum of amounts divided by count of transactions), I just wanted to point out why it probably wasn't working as you expected
I am trying to gather various KPI's for salespersons in multiple stores. The goal is to break down store performance into salesperson level.
I am facing an issue when trying to add a hitrate, as this is normally only by store. Number of quotes given / Visitors.
Even though it may not be 100% accurate I still wish to have the KPI by sales person. I am able to do this on a sales person level, but my subtotal for the store is incorrect, as it makes a summation of visitors by sales persons.
Monthly period is to be considered to as sales persons comes and goes throughout the period. Example of what I wish for a Subtotal for the measure "Vis". Store X 370 for month 1,2 & 3. For Store Y 395.
Vis measure = Visitor (Calculation i have tried but gives the wrong result for the store total for the period.)
I have tried various Calculate, Sum, max functions, but nothing seems to provide the result I need.
I hope that someone might be able to help me get along with this.
Example data tables is link as shown below:
enter image description here
Thanks in advance.
This sounds like a case where the HASONVALUE function would be useful.
The idea being that you would the result of that function in an if to determine if you are calculating at your sales person level or a the store level which should contain multiple salespersons. Thus you would have two different calculations, one for the sales person and store combination, and one for the Store level.
Example would be sometime like the following, in this example I am assuming you have a sales person table:
Measure:= IF( HASONEVALUE( Salesperson[Sales Person] ),
[Vis],
[Measure for subtotal]
)
[Measure for Subtotal] would just being the calculation that you want for your store total.
Of course if you filter to just a single sales person, then the totals for the store will just match that sales person.
I'm relatively new to SQL but have learned some cool stuff. I'm getting results that don't make sense. I've got a query with several subqueries and what-not but I have a windowed function that isn't working like I'm expecting.
The part that isn't working is this (simplified from the 300 line query):
SELECT AVG(table.sales_amount)
OVER (PARTITION BY table.month, table.sales_rep, table.department)
FROM table
The problem is that when I pull the data non aggregated I get a value different (107) than the above returns (95).
I've used windowed functions for COUNT and SUM and they work fine, but AVG is acting strangely. Am I missing something about how this works with AVG?
The subquery that table is a standin for looks like:
sales_rep, month, department, sales_amount
1, 2017-1, abc, 125.20
1, 2017-2, abc, 120.00
2, 2017-1, def, 100.00
...etc
Working out of Sql Server Management studio
SOLVED: I did finally figure it out, the results i was joining this subquery to had the sales rep multiple times in a month selling objects A&B which caused whoever sold both to be counted twice. whoops, my bad.
The results that you get should be the same values as in:
SELECT AVG(table.sales_amount)
FROM table
GROUP BY table.month, table.sales_rep, table.department;
Of course, the rows will be different. You need to match up the three key columns.
Based on your sample data, it looks like the partitioning keys uniquely define each row. Perhaps you really intend:
SELECT AVG(table.sales_amount) OVER () as overall_average
FROM table;
EDIT:
For the departmental average:
SELECT AVG(table.sales_amount) OVER (partition by table.department) as department_average
FROM table;
After some bruteforcing of potential errors I finally figured out the issue. I was joining that subquery to the another which had multiple instances of a sales_rep in a given month (selling objects a & b) which caused the average of those with sales of both objects to be counted twice instead of once.
so sales rep 1 sold objects a & b which made his avg count as 66% of the dept avg instead of 50%, and sales rep 2 count only 33%.
Am trying to rank groups by summing a field (not a calculated column) for each group so I get a static answer for each row in my table.
For example, I may have a table with state, agent, and sales. Sales is a field, not a measure. There can be many agents within a state, so there are many rows for each individual state. I am trying to rank the states by total sales within each state.
I have tried many things, but the ones that make the most sense to me are:
rankx(CALCULATETABLE(Table,allexcept(Table,Table[AGENT]),sum([Sales]),,DESC)
and
=rankx(SUMMARIZE(State,Table[State],"Sales",sum(Table[Sales])),[Sales])
The first one is creating a table where it sums sales without grouping by Agent. and then tries to rank based on that. I get #ERROR on this one.
The second one creates a table using SUMMARIZE with only sum of Sales grouped by state, then tries to take that table and rank the states based on Sales. For this one I get a rank of 1 for every row.
I think, but am not sure, that my problem is coming from the sales being a static field and not a calculated measure. I can't figure out where to go from here. Any help?
Assuming your data looks something like this...
...have you tried this:
Ranking Measure = RANKX(ALL('Table'[STATE]),CALCULATE(SUM('Table'[Sales])))
The ALL('Table'[STATE]) says to rank all states. The CALCULATE(SUM('Table'[Sales])) says to rank by the sum of their sales. The CALCULATE wrapper is important; a plain SUM('Table'[Sales]) will be filtered to the current row context, resulting in every state being ranked #1. (Alternatively, you can spin off SUM('Table'[Sales]) into a separate Sales measure - which I'd recommend.)
Note: the ranks will change based on slicers/filters (e.g. a filter by agent will re-rank the states by that agent). If you're looking for a static rank of states by their total sales (i.e. not affected by filters on agent and always looking at the entire table), then try this:
Static Ranking Measure = CALCULATE([Ranking Measure], ALLEXCEPT('Table', 'Table'[State]))
This takes the same ranking measure, but removes all filters except the state filter (which you need to leave, as that's the column you're ranking by).
I did figure out a solution that's pretty simple, but it's messier than I'd like. If it's the only thing that works though, that's okay.
I created a new table with each distinct state along with a sum of sales then just do a basic RANKX on that table.
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.