To begin with, we are going to illustrate this new feature by creating a new table where four data rows will be inserted.
CREATE TABLE [Production].[Document]( [DocumentID] [int] IDENTITY(1,1) NOT NULL, [Title] [nvarchar](50) COLLATE Latin1_General_CS_AS NOT NULL, [FileName] [nvarchar](400) COLLATE Latin1_General_CS_AS NOT NULL, [FileExtension] [nvarchar](8) COLLATE Latin1_General_CS_AS NOT NULL, [Revision] [nchar](5) COLLATE Latin1_General_CS_AS NOT NULL, [ChangeNumber] [int] NOT NULL CONSTRAINT [DF_Document_ChangeNumber] DEFAULT ((0)), [Status] [tinyint] NOT NULL, [DocumentSummary] [nvarchar](max) COLLATE Latin1_General_CS_AS NULL, [ModifiedDate] [datetime] NOT NULL CONSTRAINT [DF_Document_ModifiedDate] DEFAULT (getdate()), CONSTRAINT [PK_Document_DocumentID] PRIMARY KEY CLUSTERED ( [DocumentID] ASC ) ) ON [PRIMARY]
At first, we will do it in SQL Server 2005. This is the traditional and old-fashioned way (one INSERT statement per row):
INSERT INTO [Production].[Document]([Title],[FileName],[FileExtension],[Revision],[ChangeNumber],[Status],[DocumentSummary]) VALUES ('Installing Replacement Pedals','C:DocumentsInstalling Replacement Pedals.doc','.doc','0',32,2,'Detailed instructions ...') INSERT INTO [Production].[Document]([Title],[FileName],[FileExtension],[Revision],[ChangeNumber],[Status],[DocumentSummary]) VALUES ('Introduction 1','C:DocumentsIntroduction 1.doc','.doc','4',28,2,NULL) INSERT INTO [Production].[Document]([Title],[FileName],[FileExtension],[Revision],[ChangeNumber],[Status],[DocumentSummary]) VALUES ('Lubrication Maintenance','C:DocumentsLubrication Maintenance.doc','.doc','2',11,1,'Guidelines and recommendations...') INSERT INTO [Production].[Document]([Title],[FileName],[FileExtension],[Revision],[ChangeNumber],[Status],[DocumentSummary]) VALUES ('Seat Assembly','C:DocumentsSeat Assembly.doc','.doc','8',55,2,'Worn or damaged seats...')
This is the cumbersome way by using UNION ALL clause which has sometimes poor performance:
INSERT INTO [Production].[Document]([Title],[FileName],[FileExtension],[Revision],[ChangeNumber],[Status],[DocumentSummary]) SELECT 'Installing Replacement Pedals','C:DocumentsInstalling Replacement Pedals.doc','.doc','0',32,2,'Detailed instructions ...' UNION ALL SELECT 'Introduction 1','C:DocumentsIntroduction 1.doc','.doc','4',28,2,NULL UNION ALL SELECT 'Lubrication Maintenance','C:DocumentsLubrication Maintenance.doc','.doc','2',11,1,'Guidelines and recommendations...' UNION ALL SELECT 'Seat Assembly','C:DocumentsSeat Assembly.doc','.doc','8',55,2,'Worn or damaged seats...'
Now in SQL Server 2008 we can use Row Value Constructor feature (only one INSERT statement to insert four data rows):
INSERT INTO [Production].[Document]( [Title] ,[FileName] ,[FileExtension] ,[Revision] ,[ChangeNumber] ,[Status] ,[DocumentSummary] ) VALUES ('Installing Replacement Pedals','C:DocumentsInstalling Replacement Pedals.doc','.doc','0',32,2,'Detailed instructions ...'), ('Introduction 1','C:DocumentsIntroduction 1.doc','.doc','4',28,2,NULL), ('Lubrication Maintenance','C:DocumentsLubrication Maintenance.doc','.doc','2',11,1,'Guidelines and recommendations...'), ('Seat Assembly','C:DocumentsSeat Assembly.doc','.doc','8',55,2,'Worn or damaged seats...')
As you have noticed, we do not need to use UNION ALL any longer, it allow to save a lot of time and work. It is truly useful when we need to insert much data and it also offers a remarkable performance. I hope you enjoy this new feature. Thanks for reading again!
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