Merge multiple records into one row in a table

问题:

I have a table which has multiple records of the same sales agent id but different sales amount. How can I delete the multiple rows and just have the aggregate of the total value.

Let us for example assume the table structure as follows -

SalesAgentId, SalesAgentName, SalesAmount
111         , John Doe      ,  8437.00
112         , John O Connor ,  5849.00
111         , John Doe      ,   438.00
112         , John O Connor ,  1234.00

What I would want is (even if it is into a different table) the following -

SalesAgentId, SalesAgentName, SalesAmount
111         , John Doe      ,  8875.00
112         , John O Connor ,  7083.00

Can we do this using SQL statements or should it be an Stored Procedure only? If it is using an SP, do we have to iterate through each of the records...check if it is always there, if so, just add the SalesAmount field to the existing table and implement it?

回答1:

SELECT SalesAgentId, SalesAgentName, SUM(SalesAmount) AS SalesAmount
  INTO #AggSales
  FROM Sales
 GROUP BY SalesAgentId, SalesAgentName;

TRUNCATE TABLE Sales;    

INSERT INTO Sales
SELECT * FROM #AggSales;

DROP TABLE #AggSales;

回答2:

This is the easiest way I can think of doing it:

create table #tempSales (salesagentid int, salesagentname varchar(50), salesamount money)
go

insert into #tempSales 
select salesagentid, salesagentname, sum(salesamount)
from salesTable
group by salesagentid, salesagentname
go

select *
from #tempSales

回答3:

SELECT SalesAgentID, SUM(SalesAmount) FROM Sales GROUPBY SalesAgentID

But there's something wrong here... Why your table have BOTH SalesAgentId and SalesAgentName?

It should contain only the ID, the name should be in a SalesAgent table. Then you would retrieve the name with a join