Loop Through 1 SQL Query, Instead Of Using 2 Queries - sql

Question

Below I have a variable with two basic SELECT statements. If the user can only use one variable, #StartDate, to enter a date parameter, how can a query be looped through to only use one SELECT statement instead of two like you see below. So, imagine you don't have both queries, but one query and it can only be ran once but satisfy the 2 conditions in the WHERE clauses below, which are "FullDate = #StartDate" and "Fulldate BETWEEN DATEADD(mm, DATEDIFF(mm, 0, #StartDate), 0) AND #StartDate". SO, essentially I am trying to squeeze two SELECT statements into one and provide the relevant data from both queries. UNION ALL cannot be used here.
DECLARE #StartDate DATE = '20170610'
SELECT
FirstName,
LastName,
SUM(MoneySpent) AS 'Spent'
FROM
TableOne
WHERE
FullDate = #StartDate;
GROUP BY FirstName, LastName
SELECT
FirstName,
LastName,
SUM(MoneySpent) AS 'Spent'
FROM
TableOne
WHERE
Fulldate BETWEEN DATEADD(mm, DATEDIFF(mm, 0, #StartDate), 0) AND #StartDate;
GROUP BY FirstName, LastName

Answer 1

If you have two dates #Date1 and #Date2, then you can use this:
SELECT
FirstName,
LastName,
SUM(CASE WHEN FullDate = #Date1 THEN MoneySpent ELSE 0 END) AS 'SpentDate1',
SUM(CASE WHEN FullDate = #Date2 THEN MoneySpent ELSE 0 END) AS 'SpentDate2'
FROM
TableOne
WHERE
FullDate = #Date1 OR FullDate = #Date2
GROUP BY FirstName, LastName
BTW, UNION ALL can be used as well, you just need wrap it as subquery and use additional GROUP BY

Answer 2

Something you need to know about BETWEEN is that it includes the endpoints, so you only need the second query to obtain what you are looking for.
SELECT
FirstName,
LastName,
SUM(MoneySpent) AS 'Spent'
FROM
TableOne
WHERE
Fulldate BETWEEN DATEADD(mm, DATEDIFF(mm, 0, #StartDate), 0) AND #StartDate;
GROUP BY FirstName, LastName

Answer 3

I think the first query is already covered by the second query.
SELECT FirstName ,
LastName ,
SUM(MoneySpent) AS 'Spent'
FROM TableOne
WHERE Fulldate BETWEEN DATEADD(mm, DATEDIFF(mm, 0, #StartDate), 0)
AND #StartDate
GROUP BY FirstName, LastName
But for the sake of argument, one of many options is that you can put the relevant data of each query into a temporary table.
E.g.
DECLARE #StartDate DATE = '2017.06.10';
IF ( OBJECT_ID('tempdb..#tempTbl') IS NOT NULL )
BEGIN
DROP TABLE #tempTbl
END
CREATE TABLE #tempTbl
(
ID INT IDENTITY(1, 1)
PRIMARY KEY ,
FirstName VARCHAR(100) ,
LastName VARCHAR(100) ,
Spent MONEY
)
INSERT INTO #tempTbl
( FirstName ,
LastName ,
Spent
)
SELECT FirstName ,
LastName ,
SUM(MoneySpent) AS 'Spent'
FROM TableOne
WHERE FullDate = #StartDate
INSERT INTO #tempTbl
( FirstName ,
LastName ,
Spent
)
SELECT FirstName ,
LastName ,
SUM(MoneySpent) AS 'Spent'
FROM TableOne
WHERE Fulldate BETWEEN DATEADD(mm, DATEDIFF(mm, 0, #StartDate), 0)
AND #StartDate
SELECT FirstName,LastName,Spent
FROM #tempTbl
GROUP BY FirstName, LastName

Answer 4

I think,Here you nitice that One Resultset is subset of another resultset.
In other word,Range Between condition satify equal condition.So result is not repeated.
Example using AdventureWorks2012
DECLARE #StartDate DATE = '20020224'
DECLARE #StartDate1 DATE = '20020303'
select a.BusinessEntityID
,a.RateChangeDate,sum(a.rate) Rate
from HumanResources.EmployeePayHistory a
where a.RateChangeDate
BETWEEN DATEADD(mm, DATEDIFF(mm, 0, #StartDate), 0) AND #StartDate
or a.RateChangeDate=#StartDate1
GROUP by a.BusinessEntityID,a.RateChangeDate
here Result of both date is visisble (6 rows)
if we make it this
DECLARE #StartDate DATE = '20020224'
DECLARE #StartDate1 DATE = StartDate
here since between condtion satify RateChangeDate=#StartDate1
so output is only 5 rows
so what you are thinking is cannot be achieve.
If I had same problem then I will use only select ... FullDate between
And in front end I will pull data for fulldate=#StartDate
If you really use 2 Select like now you doing then do this,
;With CTE as
(
SELECT
FirstName,
LastName,
Fulldate,
SUM(MoneySpent) AS 'Spent'
FROM
TableOne
WHERE
Fulldate BETWEEN DATEADD(mm, DATEDIFF(mm, 0, #StartDate), 0) AND #StartDate;
GROUP BY FirstName, LastName,Fulldate
)
select *,0 flg from cte
union ALL
select * ,1 flg from cte
where Fulldate=#StartDate