How to compare two tables with one table having a temporary column name

Question

I have two tables, both with columns ID_Number and version. However, the format of the ID_number is different. My goal is to compare the two tables and output any rows with the same ID_number but different versions.

The format difference is as follows:

Eg. ID number in first table is "23-4567". The corresponding ID number in the second table is "1023004567". "10" is added before the "23" and "-" is replaced with "00". It's the same for all the IDs.

First, I used "substring" to make the ID_Number from table1 to match with ID_Number from table2 and rename this new column as newIDNumber(table1), and compare newIDNumber(table1) with ID_Number(table2). The code to convert ID_Number in table1 for the above example is as such,

Eg. '10' + SUBSTRING(@ID_number, 1, 2) + '00' + SUBSTRING(@ID_number, 4,4) AS newIDNumber

Now I write the following code to check the version difference

  SELECT ID_Number, version, "10" + SUBSTRING(@ID_number, 1, 2) + "00" + SUBSTRING(@ID_number, 4,4) (From first table) AS newIDNumber
FROM table1 
WHERE (NOT EXISTS
        (SELECT ID_Number, version
        FROM table2 
        WHERE (table1.newIDNumber= table2.ID_Number) AND (table1.version = table2.version)

        )
        )

It outputs an error saying "Unknown column 'table1.newIDNumber' in 'where clause'". How am I able to do compare without disrupting the database (inserting newIDNumber column to table1)?

Would "declare newIDNumber" work?

Answer 1

SELECT 
    ID_Number
    , version
FROM 
    table1 
WHERE
    NOT EXISTS
    (
        SELECT  1
        FROM    table2 
        WHERE
            "10" + SUBSTRING(table1.ID_number, 1, 2)
            + "00" + SUBSTRING(table1.ID_number, 4,4) = table2.ID_Number 
            AND table1.version = table2.version
    )

Answer 2

you should throw some sample data .

Try this,

declare @t table(col1 varchar(50))
insert into @t values('23-4567')

declare @t1 table(col1 varchar(50))
insert into @t1 values('1023004567')


;With CTE as
(
select t.col1

from @t t
inner join @t1 t1
on substring(t.col1,1,charindex('-',t.col1)-1)=
substring(t1.col1,charindex('10',t1.col1)+2,charindex('00',t1.col1)-3)
where NOT EXISTS(
select * from @t1 t1
where substring(t.col1,charindex('-',t.col1)+1,len(col1))
=substring(t1.col1,charindex('00',t1.col1)+2,len(col1))
)
)

select * from cte t