创建索引，SQL优化

查看执行计划前#

--清空缓存数据
dbcc dropcleanbuffers
go
--清空缓存计划
dbcc freeproccache
go
SET STATISTICS TIME ON;
GO

SET STATISTICS IO ON;
GO

创建更新索引#

	USE XXX;
	GO
	-- create\update index 1: [IX_FileItem_XLIFFFileGuid_State]
	if exists(select * from sysindexes where name='IX_FileItem_XLIFFFileGuid_State')
	DROP  index [IX_FileItem_XLIFFFileGuid_State] ON FileItem;
	GO
	CREATE NONCLUSTERED INDEX [IX_FileItem_XLIFFFileGuid_State]
	ON [dbo].[FileItem] ([XLIFFFileGuid],[State])
	INCLUDE ([UpdatedAt],[FileGuid])
	GO


	-- create\update index 2: [IX_File_TargetType]
	if exists(select * from sysindexes where name='IX_File_TargetType')
	DROP  index [IX_File_TargetType] ON [File];
	GO
	CREATE NONCLUSTERED INDEX [IX_File_TargetType]
	ON [dbo].[File] ([TargetType])
	INCLUDE ([Guid],[TargetGuid],[SourceLanguage],[TargetLanguages])
	GO

        --查看所有索引
	--select * from sysindexes where name LIKE '%IX%'