Sarang,
I don't think you need table aliasing for such a requirement. Table aliasing is only required when you want to access the same table multiple times in the same infoset.
I don't know how you intend to identify 'Shift 1/2/3', but normally you could achieve this by creating 3 local fields in the report itself. 'Shift1tot' 'Shift2tot' 'Shift3tot' or something similar. You would write a statement that identifies the value that would be included in each one: if <condition> then the qty is the confirmed qty, else the qty is 0. The report would be a statistic and not a basic list, since you would typically have many records for each order. Below is an example of a local field I created in one of my queries.
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SAP offers a course to teach how to build queries that you might want to consider attending
BC407 - Reporting: QuickViewer, InfoSet Query and SAP Query | SAP Training and Certification Shop
Or, if you are adventurous, you can try to self-teach by studying online help
SAP Query - Tools - SAP Library
Best Regards,
DB49