SQL How to make multiple values use the same Declare Variable? [closed]

问题

I am attempting to do the following

Link two tables via a join on the same database
Take a column that exists in both FK_APPLICATIONID(with a slight difference, where one = +1 of the other I.e. Column 1 =1375 and column 2 = 1376
In one of the tables exist a reference number (QREF1234) and the other contains 11 phonenumbers
I want to be able to enter the Reference number, and it returns all 11 phonenumbers as a single declarable value.
use Select * from TableD where phonenum in (@Declared variable)

Here is what I have so far,

Use Database 1

DECLARE @Result INT;

SELECT @Result = D.PhoneNum1,phonenum2,phonenum3,etc 

FROM Table1 

JOIN  TABLE2 D on D.FK_ApplicationID= D.FK_ApplicationID

where TABLE1.FK_ApplicationID = D.FK_ApplicationID + 1 
and QREF = 'Q045569/2'
Use Database2

Select * from Table3 where PhoneNum = '@result'

The names of things like TABLE1 is not their true name

Thanks

回答1:

I think you are after something like this. You are trying to "normalize" un-normalized columns and search for all those values in another table. You need to union the results together into a temp table, then search for the values.

Use Database 1


Create Table #tmp(PhoneNums varchar(50))

INSERT INTO #tmp
SELECT D.PhoneNum1
FROM Table1 
JOIN  TABLE2 D on D.FK_ApplicationID= D.FK_ApplicationID
where TABLE1.FK_ApplicationID = D.FK_ApplicationID + 1 
and QREF = 'Q045569/2'
union
SELECT D.PhoneNum2
FROM Table1 
JOIN  TABLE2 D on D.FK_ApplicationID= D.FK_ApplicationID
where TABLE1.FK_ApplicationID = D.FK_ApplicationID + 1 
and QREF = 'Q045569/2'
union
SELECT D.PhoneNum3
FROM Table1 
JOIN  TABLE2 D on D.FK_ApplicationID= D.FK_ApplicationID
where TABLE1.FK_ApplicationID = D.FK_ApplicationID + 1 
and QREF = 'Q045569/2'

--Use Database2
--you don't need to switch databases if you use a fully qualified name like shown below.
Select * from Database2..Table3 where PhoneNum in 
(
   Select PhoneNums from #tmp
)

回答2:

No, you cannot use a variable to hold multiple values and use the IN keyword. You can pass a delimited list of values in, parse that, and then use IN with the collection of values you parsed.

In the code sample you posted, you can instead create a table variable, and select from that.

回答3:

A variable can only hold a single value. Instead of using the in operator, you could accompish this same thing with a join...

Use Database1

SELECT distinct
    T3.*
FROM 
    Table1 
    JOIN  TABLE2 D on D.FK_ApplicationID= D.FK_ApplicationID
    JOIN Database2.dbo.Table3 T3 on
        T3.PhoneNum = D.PhoneNum1
        or T3.PhoneNum = D.PhoneNum2
        or T3.PhoneNum = D.PhoneNum3
where 
    TABLE1.FK_ApplicationID = D.FK_ApplicationID + 1 
    and QREF = 'Q045569/2'

回答4:

If you don't want to type a bunch of ORs on a join you could use IN for your join.

select *
from Table3 t
left join Table2 D on t.PhoneNum in 
    (
        d.phonenum1
        , d.phonenum2
        , d.phonenum3
        , d.phonenum4
        , d.phonenum5
        , d.phonenum6
        , d.phonenum7
        , d.phonenum8
        , d.phonenum9
        , d.phonenum10
        , d.phonenum11
    )
    AND D.QREF = 'Q045569/2'

I would recommend instead that you normalize your data and then this isn't such a kludge.

来源：https://stackoverflow.com/questions/27966404/sql-how-to-make-multiple-values-use-the-same-declare-variable

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sql

sql-server

declare