CREATE VIEW in SQL Server using UNION ALL -


please consider below example:

create view vw_yearlysales select 2011 yearno, productid, sum(amount) invoicetable2011 union select 2012 yearno, productid, sum(amount) invoicetable2012 union select 2013 yearno, productid, sum(amount) invoicetable2013 go

the invoicetable2013 doesn't exist , don't want create right now, created automatically when recording first invoice year 2013.

can me on how specify condition verify existence of table before doing union all?

many help.

as others have correctly said, can't achieve view, because select statement has reference concrete set of tables - , if of them don't exist, query fail execute.

it seems me problem more fundamental. there should conceptually 1 invoicetable, rows different dates. separating out different logical tables year presumably that's been done optimisation (unless columns different, doubt).

in case, partitioning seems way remedy problem (partitioning large tables year/quarter/month canonical example). let have single invoicetable logically, yet specify sql server should store data behind scenes if different tables split out year. best of both worlds - accurate model, , fast performance - , makes view definition simple.


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