Para los futuros estudiantes del curso "Desarrollador de MS SQL Server", preparamos una traducción de un artículo útil.
También invitamos a todos a un seminario web abierto sobre el tema "Polybase: la vida antes y después" . En el seminario web, veremos cómo era posible interactuar con otras bases de datos antes de Polybase y cómo funciona ahora.
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USE StackOverflow;
GO
/* Create date partition function by day since Stack Overflow's origin,
modified from Microsoft Books Online:
https://docs.microsoft.com/en-us/sql/t-sql/statements/create-partition-function-transact-sql?view=sql-server-ver15#BKMK_examples
DROP PARTITION SCHEME [DatePartitionScheme];
DROP PARTITION FUNCTION [DatePartitionFunction];
*/
DECLARE @DatePartitionFunction nvarchar(max) =
N'CREATE PARTITION FUNCTION DatePartitionFunction (datetime)
AS RANGE RIGHT FOR VALUES (';
DECLARE @i datetime = '2008-06-01';
WHILE @i <= GETDATE()
BEGIN
SET @DatePartitionFunction += '''' + CAST(@i as nvarchar(20)) + '''' + N', ';
SET @i = DATEADD(DAY, 1, @i);
END
SET @DatePartitionFunction += '''' + CAST(@i as nvarchar(20))+ '''' + N');';
EXEC sp_executesql @DatePartitionFunction;
GO
/* Create matching partition scheme, but put everything in Primary: */
CREATE PARTITION SCHEME DatePartitionScheme
AS PARTITION DatePartitionFunction
ALL TO ( [PRIMARY] );
GO
Users, CreationDate:
DROP TABLE IF EXISTS dbo.Users_partitioned;
GO
CREATE TABLE [dbo].[Users_partitioned](
[Id] [int] NOT NULL,
[AboutMe] [nvarchar](max) NULL,
[Age] [int] NULL,
[CreationDate] [datetime] NOT NULL,
[DisplayName] [nvarchar](40) NOT NULL,
[DownVotes] [int] NOT NULL,
[EmailHash] [nvarchar](40) NULL,
[LastAccessDate] [datetime] NOT NULL,
[Location] [nvarchar](100) NULL,
[Reputation] [int] NOT NULL,
[UpVotes] [int] NOT NULL,
[Views] [int] NOT NULL,
[WebsiteUrl] [nvarchar](200) NULL,
[AccountId] [int] NULL
) ON [PRIMARY];
GO
CREATE CLUSTERED INDEX CreationDate_Id ON
dbo.Users_partitioned (Id)
ON DatePartitionScheme(CreationDate);
GO
INSERT INTO dbo.Users_partitioned (Id, AboutMe, Age,
CreationDate, DisplayName, DownVotes, EmailHash,
LastAccessDate, Location, Reputation, UpVotes,
Views, WebsiteUrl, AccountId)
SELECT Id, AboutMe, Age,
CreationDate, DisplayName, DownVotes, EmailHash,
LastAccessDate, Location, Reputation, UpVotes,
Views, WebsiteUrl, AccountId
FROM dbo.Users;
GO
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Users Users_partitioned. , Users_partitioned , , , :
CREATE INDEX DisplayName ON dbo.Users(DisplayName);
CREATE INDEX DisplayName ON dbo.Users_partitioned(DisplayName);
, :
SET STATISTICS TIME, IO ON;
SELECT * FROM dbo.Users WHERE DisplayName = N'Brent Ozar';
GO
SELECT * FROM dbo.Users_partitioned WHERE DisplayName = N'Brent Ozar';
GO
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Users_partitioned . , ON PRIMARY , .
CREATE INDEX DisplayName ON dbo.Users(DisplayName); CREATE INDEX DisplayName ON dbo.Users_partitioned(DisplayName) ON [PRIMARY];
:
SET STATISTICS TIME, IO ON;
SELECT * FROM dbo.Users WHERE DisplayName = N'Brent Ozar';
GO
SELECT * FROM dbo.Users_partitioned WHERE DisplayName = N'Brent Ozar';
GO
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