SQL Get MODE Instead of AVG - sql-server

Question

I have a stored procedure which returns me the average issue price of products. There will be multiple rows for each issue, and so I group by barcode, and also the number of stores that have inserted a row for this issue, and get the average of IssuePrice as this comes from user input:
ALTER PROCEDURE [dbo].[GetUnknownBarcodeReport]
#Status INT,#StoreTypeID INT
AS
BEGIN
SELECT COUNT(StoreCode) AS [# Stores]
,MAX(IssueName) AS IssueName
,AVG(IssuePrice) AS IssuePrice
,Barcode
,Product.EAN13 AS [Matched Product Code]
,Product.Name AS [Matched Product Name]
,Product.MainCatagory AS [Product Catagory]
FROM UnknownBarcodes
LEFT JOIN Product on LEFT(UnknownBarcodes.Barcode,13) = Product.EAN13
WHERE UnknownBarcodeStatusID = #Status
AND LEN(Barcode) >= 10
AND StoreTypeID = #StoreTypeID
GROUP BY Barcode, Product.EAN13, Product.Name, Product.MainCatagory
ORDER BY
CASE WHEN #status = 1 THEN
COUNT(StoreCode)
WHEN #status = 2 THEN
COUNT(StoreCode)
WHEN #status = 3 THEN
MAX(DateInserted)
END DESC
END
The same product can be reported multiple times and therefore have multiple rows, but sometimes users will enter different prices. If ten users all enter the same barcode and say the price is 100 then the AVG(IssuePrice) is also 100. However, if 9 enter 100, and the last row is entered as 1 then the AVG changes to 90.1
I would like to replace the AVG with the mathematical equivalent of MODE so that the above example would still return 100 because there are more 100s reported than any other value. Is this possible in SQL?
To help re-create this, the script for the table is below:
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
SET ANSI_PADDING ON
GO
CREATE TABLE [dbo].[UnknownBarcodes](
[ID] [int] IDENTITY(1,1) NOT NULL,
[StoreCode] [int] NULL,
[DateInserted] [datetime] NULL,
[StoreTypeID] [int] NULL,
[Barcode] [varchar](100) NULL,
[UnknownBarcodeStatusID] [int] NULL,
[StatusDescription] [varchar](1000) NULL,
[IssueName] [varchar](100) NULL,
[IssuePrice] [int] NULL,
[AutoReported] [bit] NULL,
CONSTRAINT [PK_UnknownBarcodes] PRIMARY KEY CLUSTERED
(
[ID] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON)
)
GO
SET ANSI_PADDING OFF
GO
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
SET ANSI_PADDING ON
GO
CREATE TABLE [dbo].[Product](
[EAN13] [bigint] NOT NULL,
[Name] [varchar](250) NULL,
[MainCatagory] [varchar](100) NULL,
CONSTRAINT [PK_Product] PRIMARY KEY CLUSTERED
(
[EAN13] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON)
)
GO
SET ANSI_PADDING OFF
GO
INSERT INTO [dbo].[UnknownBarcodes] ([StoreCode],[DateInserted],[StoreTypeID],[Barcode],[UnknownBarcodeStatusID],[StatusDescription],[IssueName],[IssuePrice],[AutoReported]) VALUES (412,2015-07-15 08:01:03.817,1,'977096171301112',3,'Scanning issues regarding the reported unknown item','ASIAN TRADER FREE TRADE',200,1)
INSERT INTO [dbo].[UnknownBarcodes] ([StoreCode],[DateInserted],[StoreTypeID],[Barcode],[UnknownBarcodeStatusID],[StatusDescription],[IssueName],[IssuePrice],[AutoReported]) VALUES (843,2015-07-15 08:01:03.817,1,'977096171301112',3,'Scanning issues regarding the reported unknown item','ASIAN TRADER FREE TRADE',10,1)
INSERT INTO [dbo].[UnknownBarcodes] ([StoreCode],[DateInserted],[StoreTypeID],[Barcode],[UnknownBarcodeStatusID],[StatusDescription],[IssueName],[IssuePrice],[AutoReported]) VALUES (860,2015-07-15 08:01:03.817,1,'977096171301112',3,'Scanning issues regarding the reported unknown item','ASIAN TRADER FREE TRADE',10,1)
INSERT INTO [dbo].[UnknownBarcodes] ([StoreCode],[DateInserted],[StoreTypeID],[Barcode],[UnknownBarcodeStatusID],[StatusDescription],[IssueName],[IssuePrice],[AutoReported]) VALUES (864,2015-07-15 08:01:03.817,1,'977096171301112',3,'Scanning issues regarding the reported unknown item','ASIAN TRADER FREE TRADE',10,1)
INSERT INTO [dbo].[UnknownBarcodes] ([StoreCode],[DateInserted],[StoreTypeID],[Barcode],[UnknownBarcodeStatusID],[StatusDescription],[IssueName],[IssuePrice],[AutoReported]) VALUES (964,2015-07-15 08:01:03.817,1,'977096171301112',3,'Scanning issues regarding the reported unknown item','ASIAN TRADER FREE TRADE',10,1)
INSERT INTO [dbo].[UnknownBarcodes] ([StoreCode],[DateInserted],[StoreTypeID],[Barcode],[UnknownBarcodeStatusID],[StatusDescription],[IssueName],[IssuePrice],[AutoReported]) VALUES (1061,2015-07-15 08:01:03.817,1,'977096171301112',3,'Scanning issues regarding the reported unknown item','ASIAN TRADER FREE TRADE',10,1)
INSERT INTO [dbo].[UnknownBarcodes] ([StoreCode],[DateInserted],[StoreTypeID],[Barcode],[UnknownBarcodeStatusID],[StatusDescription],[IssueName],[IssuePrice],[AutoReported]) VALUES (1350,2015-07-15 08:01:03.817,1,'977096171301112',3,'Scanning issues regarding the reported unknown item','ASIAN TRADER FREE TRADE',10,1)
INSERT INTO [dbo].[UnknownBarcodes] ([StoreCode],[DateInserted],[StoreTypeID],[Barcode],[UnknownBarcodeStatusID],[StatusDescription],[IssueName],[IssuePrice],[AutoReported]) VALUES (1375,2015-07-15 08:01:03.817,1,'977096171301112',3,'Scanning issues regarding the reported unknown item','ASIAN TRADER FREE TRADE',10,1)
INSERT INTO [dbo].[UnknownBarcodes] ([StoreCode],[DateInserted],[StoreTypeID],[Barcode],[UnknownBarcodeStatusID],[StatusDescription],[IssueName],[IssuePrice],[AutoReported]) VALUES (1489,2015-07-15 08:01:03.817,1,'977096171301112',3,'Scanning issues regarding the reported unknown item','ASIAN TRADER FREE TRADE',10,1)
INSERT INTO [dbo].[UnknownBarcodes] ([StoreCode],[DateInserted],[StoreTypeID],[Barcode],[UnknownBarcodeStatusID],[StatusDescription],[IssueName],[IssuePrice],[AutoReported]) VALUES (1531,2015-07-15 08:01:03.817,1,'977096171301112',3,'Scanning issues regarding the reported unknown item','ASIAN TRADER FREE TRADE',10,1)
You can see that the MODE of the above set should be 10 even though one row has a value of 200 which skews the AVG

Answer 1

From: http://blogs.lessthandot.com/index.php/datamgmt/datadesign/calculating-mean-median-and-mode-with-sq/
MODE
To Calculate the mode with sql server, we first need to get the counts for each value in the set. Then, we need to filter the data so that values equal to the count are returned.
Declare #Temp Table(Id Int Identity(1,1), Data Decimal(10,5))
Insert into #Temp Values(1)
Insert into #Temp Values(2)
Insert into #Temp Values(5)
Insert into #Temp Values(5)
Insert into #Temp Values(5)
Insert into #Temp Values(6)
Insert into #Temp Values(6)
Insert into #Temp Values(6)
Insert into #Temp Values(7)
Insert into #Temp Values(9)
Insert into #Temp Values(10)
Insert into #Temp Values(NULL)
SELECT TOP 1 with ties DATA
FROM #Temp
WHERE DATA IS Not NULL
GROUP BY DATA
ORDER BY COUNT(*) DESC
In your example the functional sql could be accomplished by a subquery:
(select top 1 IssuePrice from UnknownBarcodes barx where barx.BarCode = bar.Barcode group by barx.IssuePrice order by count(*) DESC ) IssuePrice_MODE
Total query:
declare #Status int, #StoreTypeId int;
set #Status = 3;
set #StoreTypeId = 1;
SELECT
COUNT(bar.StoreCode) AS [# Stores]
,MAX(bar.IssueName) AS IssueName
,AVG(bar.IssuePrice) AS IssuePrice
,(select top 1 IssuePrice from UnknownBarcodes barx where barx.BarCode = bar.Barcode group by barx.IssuePrice order by count(*) DESC ) IssuePrice_MODE
,bar.Barcode
,Product.EAN13 AS [Matched Product Code]
,Product.Name AS [Matched Product Name]
,Product.MainCatagory AS [Product Catagory]
FROM UnknownBarcodes bar
LEFT JOIN Product on LEFT(bar.Barcode,13) = Product.EAN13
WHERE bar.UnknownBarcodeStatusID = #Status
AND LEN(bar.Barcode) >= 10
AND bar.StoreTypeID = #StoreTypeID
GROUP BY bar.Barcode, Product.EAN13, Product.Name, Product.MainCatagory
ORDER BY
CASE WHEN #status = 1 THEN
COUNT(bar.StoreCode)
WHEN #status = 2 THEN
COUNT(bar.StoreCode)
WHEN #status = 3 THEN
MAX(bar.DateInserted)
end
DESC
The query below might be a bit more efficient on large datasets since it restricts the results that have to be iterated
declare #Status int, #StoreTypeId int;
set #Status = 3;
set #StoreTypeId = 1;
with FirstQuery as (SELECT
*
FROM UnknownBarcodes bar
LEFT JOIN Product on LEFT(bar.Barcode,13) = Product.EAN13
WHERE bar.UnknownBarcodeStatusID = #Status
AND LEN(bar.Barcode) >= 10
AND bar.StoreTypeID = #StoreTypeID
)
select COUNT(StoreCode) AS [# Stores]
,MAX(IssueName) AS IssueName
,AVG(IssuePrice) AS IssuePrice
,Barcode
,(select top 1 IssuePrice from FirstQuery barx where barx.BarCode = FirstQuery.Barcode group by barx.IssuePrice order by count(*) DESC ) IssuePrice_MODE
,EAN13 AS [Matched Product Code]
,Name AS [Matched Product Name]
,MainCatagory AS [Product Catagory]
from FirstQuery
GROUP BY Barcode, EAN13, Name, MainCatagory
ORDER BY
CASE WHEN #status = 1 THEN
COUNT(StoreCode)
WHEN #status = 2 THEN
COUNT(StoreCode)
WHEN #status = 3 THEN
MAX(DateInserted)
END DESC

Answer 2

I have use inner query to calculate MODE.
SELECT COUNT(StoreCode) AS [# Stores]
,MAX(IssueName) AS IssueName
,AVG(IssuePrice) AS IssuePrice,
(select top 1 issuePrice from [UnknownBarcodes] where ID = UnknownBarcodes.id group by IssuePrice having IssuePrice > 1) issuePrice_MODE
,Barcode
,Product.EAN13 AS [Matched Product Code]
,Product.Name AS [Matched Product Name]
,Product.MainCatagory AS [Product Catagory]
FROM UnknownBarcodes
LEFT JOIN Product on LEFT(UnknownBarcodes.Barcode,13) = Product.EAN13
WHERE UnknownBarcodeStatusID = 3
AND LEN(Barcode) >= 10
AND StoreTypeID = 1
GROUP BY Barcode, Product.EAN13, Product.Name, Product.MainCatagory

Answer 3

How does this work for what you are after? No idea how well it will perform on larger datasets though:
;with cte as
(
select count(1) over (partition by b.IssueName
,p.EAN13
,p.Name
,p.MainCatagory
) as [# Stores]
,b.IssueName
,b.IssuePrice
,row_number() over (partition by b.IssueName
,p.EAN13
,p.Name
,p.MainCatagory
order by count(1) desc
) as IssuePriceSort
,b.Barcode
,p.EAN13
,p.Name
,p.MainCatagory
from UnknownBarcodes as b
left join Product as p
on left(b.Barcode,13) = p.EAN13
where UnknownBarcodeStatusID = #Status
and len(Barcode) >= 10
and StoreTypeID = #StoreTypeID
group by b.Barcode
,b.IssueName
,b.IssuePrice
,p.EAN13
,p.Name
,p.MainCatagory
)
select [# Stores]
,[IssueName]
,[IssuePrice]
,[IssuePriceSort]
,[Barcode]
,[EAN13]
,[Name]
,[MainCatagory]
from cte
where IssuePriceSort = 1