Question

Assuming I have a table SomeTable with the following data:

Primary Key    Column1    Column2    Column3    Column4    Column5    Num
    1           dat1       abc1       dat3       dat4       por7       1
    2           dat1       gcd4       dat3       dat4       yrt8       6
    3           dat1       iut7       dat3       dat4       asd6       2  
    4          other1     other2     other3     other4     other5      4 

Another table SomeTableGrouped with a “Group Byed” version created using a query like this:

INSERT INTO SomeTableGrouped
SELECT Column1, Column3, Column4, SUM(Num)
FROM SomeTable
GROUP BY Column1, Column3, Column4

Primary Key    Column1    Column3    Column4    Num
    100         dat1       dat3       dat4       9
    200        other1     other3     other4      4 

What I’d like to be able to do is, if I have a primary key of SomeTableGrouped, I need to be able to tell which specific rows from SomeTable it came from.

Example:

In a separate table RandomTable, I have data like this:

Primary Key    Column1    SomeTableGroupedId
    1           dat1             100
    2           dat2             100

If I look at the first row, I need to be able to list out row 1 – 3 from SomeTable

How can I do this? I can’t change the schema very much (ie. I can only add new columns, remove columns, add a new table) so a dirty solution is perfectly fine with me.

Answer 1

I think this is what you want.

SELECT id
FROM SomeTable
INNER JOIN SomeTableGrouped ON
    (SomeTable.Column1 = SomeTableGrouped.Column1) AND
    (SomeTable.Column2 = SomeTableGrouped.Column2) AND
    (SomeTable.Column3 = SomeTableGrouped.Column3) 
WHERE SomeTableGrouped.id = ...