SQL Saturday #100 Brazil Windowing Functions no SQL Server 2012 SELECT * FROM (VALUES('Fabiano Neves Amorim'), ('Sr.Nimbus – SQL Server MVP'),

Apresentação em tema: "SQL Saturday #100 Brazil Windowing Functions no SQL Server 2012 SELECT * FROM (VALUES('Fabiano Neves Amorim'), ('Sr.Nimbus – SQL Server MVP'),"— Transcrição da apresentação:

1 SQL Saturday #100 Brazil Windowing Functions no SQL Server 2012 SELECT * FROM (VALUES('Fabiano Neves Amorim'), ('Sr.Nimbus – SQL Server MVP'), ('fabiano.amorim@srnimbus.com.br | @mcflyamorim'), ('http://blogfabiano.com')) AS Tab("Sobre mim:")

2 Patrocinadores

3 Agenda  Set Based vs Row by Row  O que são windows functions?  Novas funções implementadas no SQL2012  O que ainda falta?  Window Frame  Demos  Perguntas e respostas

4 Set Based vs Row by Row

5 O que são windows functions? Similar as funções de agregação Retornam um valor a partir de dados agregados Padrão SQL:2008 Suportado no Oracle, DB2, PostegreSQL It’s all about Sets

6 Clausula OVER SELECT ID_Conta, DT_Lancamento, VL_Lancamento, SUM(VL_Lancamento) OVER(PARTITION BY ID_Conta ORDER BY DT_Lancamento RANGE BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW) FROM tbLancamentos GO PARTITION BY Default WINDOW FRAME ORDER BY função de agregação + partition by + order by + window frame

7 SQL Server 2012  Suporte quase completo a clausula OVER()  Order by  Partition By  Window frame  Novas functions: LEAD(), LAG(), FISRT_VALUE(), LAST_VALUE(), CUME_DIST(), PERCENT_RANK(), PERCENTILE_CONT(), PERCENTILE_DISC()

8 Window Frame [ROWS | RANGE] BETWEEN AND UNBOUNDED PECEDING: Window inicia na primeira linha da partição. CURRENT ROW: Window inicia na linha atual. PRECEDING ou FOLLOWING UNBOUNDED FOLLOWING: Window termina na última linha da partição. CURRENT ROW: Window termina na linha atual. PRECEDING ou FOLLOWING

9 Window Frame, duas “janelas” USE NorthWind GO SELECT OrderID, CustomerID FROM Orders WHERE CustomerID IN (1,2) ORDER BY CustomerID

10 Window Frame, “janelas” coexistem

11 Window Frame – First_Value SELECT OrderID, CustomerID, FIRST_VALUE(OrderID) OVER(PARTITION BY CustomerID ORDER BY OrderID) AS FirstOrderID FROM Orders WHERE CustomerID IN (1,2)

12 Window Frame – Last_Value SELECT OrderID, CustomerID, LAST_VALUE(OrderID) OVER(PARTITION BY CustomerID ORDER BY OrderID) AS FirstOrderID FROM Orders WHERE CustomerID IN (1,2)

13 Window Frame – Last_Value …LAST_VALUE(OrderID) OVER(PARTITION BY CustomerID ORDER BY OrderID ROWS BETWEEN UNBOUNDED PRECEDING AND UNBOUNDED FOLLOWING) AS FirstOrderID...

14 Demonstração

15 O que ainda falta no SQL2012?  Funções:  FIRST, retorna o primeiro valor de um grupo ordenado MAX(Cidade) KEEP (DENSE_RANK FIRST ORDER BY SUM(Valor_Pedido))*  LAST: último valor de um grupo ordenado MIN(Cidade) KEEP (DENSE_RANK LAST ORDER BY SUM(Valor_Pedido))*  NULLs FIRST, NULLs LAST  OVER(ORDER BY Coluna1 NULLs FIRST)  Interval (Year, Month, Day, Hour, Minute, Second)  Window Clause * não standard SELECT LAG(Col1) OVER MinhaWin AS Col1 FROM Tabela1 WINDOW MinhaWin AS (ORDER BY Coluna1 ROWS 2 PRECEDING)

16 Recursos  Treinamentos Sr.Nimbus  http://www.srnimbus.com.br/ http://www.srnimbus.com.br/  Artigos simple-talk:  http://tinyurl.com/SQLSat100-WF1 http://tinyurl.com/SQLSat100-WF1  http://tinyurl.com/SQLSat100-WF2 http://tinyurl.com/SQLSat100-WF2  Artigos meu blog:  http://blogfabiano.com/category/windows- functions/ http://blogfabiano.com/category/windows- functions/  Video SQL Bits IX  Dave Ballantyne http://www.sqlbits.com/Sessions/Event9/Whats_n ew_in_Denali-TSQL http://www.sqlbits.com/Sessions/Event9/Whats_n ew_in_Denali-TSQL

17 Dúvidas e brindes! ? SELECT "Sobre Mim:" FROM (VALUES('Fabiano Neves Amorim'), ('Sr.Nimbus – SQL Server MVP'), ('fabiano.amorim@srnimbus.com.br|@mcflyamorim'), ('http://blogfabiano.com')) AS Tab("Sobre mim:")