Alternate for this code(joins)

Question

CREATE TABLE [Store](
[StoreId] [int] IDENTITY(1,1) NOT NULL,
[LOC_Name] [varchar](50) NULL,
CONSTRAINT [PK_Store] PRIMARY KEY CLUSTERED
[StoreId] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY]
Insert into [dbo].[Store]
[LOC_Name]
select 'virginia'
union all
select 'chicago'
CREATE TABLE [Employee](
[StoreId] [int] NOT NULL,
[Emp_NAME] [nvarchar](70) NULL,
) ON [PRIMARY]
Insert into [dbo].[Employee]
[StoreId]
,[Emp_NAME]
select 1,'daniel'
union all
select 1,'jack'
union all
select 1,'roger'
union all
select 1,'matt'
union all
select 2,'sam'
union all
select 2,'henry'
union all
select 2,'eston'
union all
select 2,'robert'
union all
select 2,'nadal'
CREATE TABLE [Customer](
[CustomerId] [int] IDENTITY(1,1) NOT NULL,
[StoreId] [int] NOT NULL,
[CUST_NO] [nvarchar](11) NULL,
CONSTRAINT [PK_Customer] PRIMARY KEY CLUSTERED
[CustomerId] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY]
set identity_insert [CCC_STAGE].[dbo].[Customer_test] on
Insert into [CCC_STAGE].[dbo].[Customer_test]
[CustomerId]
,[StoreId]
,[CUST_NO]
select 201,1,897456
union all
select 202,1,974652
union all
select 203,1,276294
union all
select 204,1,612348
union all
select 205,2,187906
union all
select 206,2,289123
union all
select 207,2,427403
union all
select 208,2,591654
union all
select 209,2,904563
-------------- Query to retrieve In each location each employee is working on how many customers--
select [LOC_NAME],
B.[Emp_NAME],
COUNT(distinct C.[CUST_NO]) TOTAL_CUSTOMERS
FROM [CCC_STAGE].[dbo].[Store] A
join [CCC_STAGE].[dbo].[Employee] B
on A.StoreId=B.StoreId
join [CCC_STAGE].[dbo].[Customer] c
on B.StoreId=C.StoreId
--where LOC_NAME='virginia'
--where LOC_NAME='chicago'
group by [LOC_NAME]
,B.[Emp_NAME]
ORDER BY [LOC_NAME],B.[Emp_NAME]
Hi Everyone,
I inserted the code creating tables and inserting values to tables and also there is a query which retrieves the data from the tables I created.
In this scenario, what we need to get is.....
we need to find out in each location, each employee is working on how many customers, but with the query I wrote I get the data like, all the employee's are working on all the customers. Below is the output I should get
loc_name emp_name  total_customers
chiacgo    eston             1
Chicago    henry             2
Chicago    nadal             2
Chicago    Robert          1
but I am getting the below output which is in correct
loc_name emp_name  total_customers
chiacgo    eston            5
Chicago      henry         5
Chicago    nadal           5
Chicago    Robert         5
Why I am getting this out put can any one tell me please.... I am getting an out put like all the employees are working on all the customers.
Thanks
vishu

Answer 1

Thank you for trying to post DDL; unfortunately, you got it wrong. You also writer really bad SQL code. Only one store and one Personnel? And Personnel is not an attribute of store! We do not use IDENTITY in RDBMS, etc. 
CREATE TABLE Stores
(store_duns CHAR(9) NOT NULL PRIMARY KEY, -- wrong!
 store_location VARCHAR(50) NOT NULL);
The DUNS is the industry standard for a business identifier, but let's keep your INTEGER for now. A location should be on the same scale – that means a city-state location name. 
Do you really have only one employee, as you said? Why do you think a store is an attribute of this one guy? You have a relationship table here. Tables must have keys. 
Why did you use a emp_name NVARCHAR(70) as a key?? 
CREATE TABLE Store_Assignments 
(emp_id CHAR(10) NOT NULL 
  REFERENCES Personnel (emp_id)
  PRIMARY KEY, 
 store_duns CHAR(9) NOT NULL
  REFERENCES Stores(store_duns));
Customers also do not have a store as an attribute! They have a relationship. Is it 1:1, 1:m, n:m or what?? I will guess 1:1. D ou know what that means? You seem to have no idea how to write a basic schema. 
CREATE TABLE Customer_Assignments 
(customer_id CHAR(16) NOT NULL PRIMARY KEY
  REFERENCES Customers(customer_id)
 ON DELETE CASCADE , 
 store_duns CHAR(9) NOT NULL
  REFERENCES Stores(store_duns)
 ON DELETE CASCADE);
>> we need to find out in each location, each employee is working on how many customers, but with the query I wrote I get the data like, all the employee’s are working on all the customers. <<
Your design is garbage. Where did you assign a customer to an employee? (“Hello, my name is Joe and I will be your salesman/waiter!”). The location of a store is unimportant for this.  You need:
CREATE TABLE Customer_Agent
(customer_id CHAR(16) NOT NULL PRIMARY KEY
  REFERENCES Customers(customer_id)
 ON DELETE CASCADE, 
 emp_id CHAR(9) NOT NULL
  REFERENCES Personnel(emp_id)
 ON DELETE CASCADE);
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