SQL where customer_id in (xx)

Question

Could really use your help!

I have a query:

Select *
from Customers
Where Customer_id in (001,002,003)

...you get the idea.

My problem is, if there is no record for customer_id 003 for example, no record is displayed. How can i display "003" and state that no record was found? I would prefer this than having no record display at all.

Thanking you in advance!

Answer 1

In SQL Server 2008+ you can use

SELECT V.Customer_id,
       C.*
FROM   (VALUES(1),
              (2),
              (3)) V(Customer_id)
       LEFT JOIN Customers C
         ON C.Customer_id = V.Customer_id 

Non matching values will have NULL in the C.Customer_id column.

Answer 2

Usually for this sort of thing I have a function which takes a csv and returns a table for me. Then I do something like the following.

-- this is creating the temporary table which would normally be created by a function.
DECLARE @Temp TABLE (Customer_id int)
INSERT INTO @Temp(Customer_id)
SELECT 1
INSERT INTO @Temp(Customer_id)
SELECT 2
INSERT INTO @Temp(Customer_id)
SELECT 3

-- now do the select statement.
SELECT 
    T.Customer_id,
     C.*
FROM
    Customers C
RIGHT OUTER JOIN
     @Temp T
ON
     T.Customer_id = C.Customer_id

This will then give you results whereby if the C.Customer_id is NULL then it is not an Id that exists in your Customer table . This does the same job as @MartinSmith did, but is supported by most SQL server versions.

Answer 3

In oracle you can do something like this:

with vals as
 (SELECT '001' as val
    from dual
  union
  select '002'
    from dual
  union
  select '030' from dual)
select v.val, nvl(c.Customer_id, 'no Customer found') from vals v left join Customers c on c.Customer_id = v.val

Answer 4

What you would need to do is query against a list of the customer IDs you want to look up (including those that may not exist) and then left join this with your customers table. Creating a temporary table of customer IDs that you want to query against is platform specific, but here is how I would do it in Oracle:

with customersToLookup as (
  select '001' as customer_id from dual union all
  select '002' as customer_id from dual union all
  select '003' as customer_id from dual
)
select    customersToLookup.customer_id,
          customers.*
from      customersToLookup
left join customers
on        customers.customer_id = customersToLookup.customer_id;

It's very unusual, in my experience, to run a query like this: RDBMs aren't meant to be used in this way.

Answer 5

Probably not the best solution because of complexity and clearly not recommended for tables with a lot of rows, but.. I created 2 new temporary tables: #tempTab2(in which I saved the id's that have been sent) and #tempTabFinal (in which I saved the row coresponding to that ID if the ID exist, and a "not found message" if not).Here is a print screen to see if this is what you what to do, and the code (I used for test the 'questions' table, which has as columns: q_id and question - the actual question)

DECLARE @INSTR as VARCHAR(MAX)
SET @INSTR = '1,153,154,1555,111,'
DECLARE @SEPERATOR as VARCHAR(1)
DECLARE @SP INT
DECLARE @VALUE VARCHAR(1000)
SET @SEPERATOR = ','
CREATE TABLE #tempTab2 (id int not null,question varchar(60))
CREATE TABLE #tempTabFinal(id varchar(40) not null,question varchar(60))

WHILE PATINDEX('%' + @SEPERATOR + '%', @INSTR ) <> 0 
BEGIN
   SELECT  @SP = PATINDEX('%' + @SEPERATOR + '%',@INSTR)
   SELECT  @VALUE = LEFT(@INSTR , @SP - 1)
   SELECT  @INSTR = STUFF(@INSTR, 1, @SP, '')
   INSERT INTO #tempTab2 (id,question) VALUES (@VALUE,'question')
END

DECLARE @INDEX INT
SET @INDEX = 1

WHILE (@INDEX <=5)
BEGIN
    IF((Select COUNT(*) FROM questions Where q_id=  (SELECT TOP 1 id from #tempTab2)) >0   )
    BEGIN
        DECLARE @TEMP as varchar (80)
        SET @TEMP = (Select question from questions where q_id = (SELECT TOP 1 id from #tempTab2))
        DECLARE @ID INT 
        SET @ID = (SELECT TOP 1 id from #tempTab2)

        Insert into #tempTabFinal Values(@ID,@Temp)

    END
    ELSE    
    BEGIN
        DECLARE @NOTFND as Varchar(20)
        SET @NOTFND = (SELECT TOP 1 id from #tempTab2)
        Insert into #tempTabFinal Values('id ' +@NOTFND + ' Not found ','Not found')
    END

    DELETE TOP (1) from #tempTab2
    SET @INDEX = @INDEX + 1
END

Select * from #tempTabFinal
DROP TABLE #tempTab2
DROP TABLE #tempTabFinal