For future students on the course "MS SQL Server Developer" we prepared a translation of a useful article.
We also invite everyone to an open webinar on the topic "Polybase: life before and after . " At the webinar, we will look at how it was possible to interact with other databases before Polybase, and how it works now.
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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
Let’s c
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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