2。将结构化数据和非结构化数据都存储在数据库中,多年以来,数据库一直都支持存储非关系数据,如二进制大对象,或BLOB,SQL Server称之为varbinary数据类型,这样的好处是能充分利用数据库的特性(如事务支持,备份和恢复支持,集成安全性的支持,全文搜索支持等),但成本费用会更高,所需的磁盘空间更多,因为是存储在同一行数据里,存储和检索时间更长,对应用程序的整体性能也会有负面影响。(如果你写查询时用select * from xxx 就很慢了)
3。SQL Server 2008中引入的FILESTREAM数据类型来存储非结构化数据,如文档,演示文稿,视频,音频,图像,数据库中存储的是文件系统上的一个指针。在SQL Server 2008中,新的FILESTREAM(文件流)特性是在现有的varbinary(max)数据类型之上实现的,你可以在服务器的文件系统上存储真实的数据,但可以在数据库上下文内管理和访问。自动保证了事务的完整性。
4。SQL Server 2012的FileTable则进一步增强,它可以让应用程序通过引入FileTable整合其存储和数据管理组件,允许非事务性访问,提供集成的对非结构化数据和元数据的全文搜索和语义搜索 。
USE master GO
EXEC sp_configure 'filestream access level', 2
Go
RECONFIGURE GO
--You can use this statement to see current
--config value and running value
EXEC sp_configure filestream_access_level;
GO 创建LearnFileTable数据库
USE master
GO
IF EXISTS (SELECT name FROM sys.databases WHERE name = N'LearnFileTable')
DROP DATABASE LearnFileTable
GO
CREATE DATABASE LearnFileTable
--Details of primary file group
ON PRIMARY
( NAME = LearnFileTable_Primary,
FILENAME =N'D:\FileTable\LearnFileTable_Data.mdf',
SIZE = 10MB,
MAXSIZE = 50MB,
FILEGROWTH = 5MB),
--Details of additional filegroup to be used to store data
FILEGROUP DataGroup
( NAME = LearnFileTable_Data,
FILENAME =N'D:\FileTable\LearnFileTable_Data.ndf',
SIZE = 10MB,
MAXSIZE = 50MB,
FILEGROWTH = 5MB),
--Details of special filegroup to be used to store FILESTREAM data
FILEGROUP FSDataGroup CONTAINS FILESTREAM
( NAME = FileStream,
--FILENAME refers to the path and not to the actual file name. It
--creates a folder which contains a filestream.hdr file and
--also a folder $FSLOG folder as depicted in image below
FILENAME =N'D:\FileTable\FSData')
--Details of log file
LOG ON
(Name = LearnFileTable_Log,
FILENAME = 'D:\FileTable\LearnFileTable_Log.ldf',
SIZE = 5MB,
MAXSIZE = 25MB,
FILEGROWTH = 5MB
)
WITH FILESTREAM (NON_TRANSACTED_ACCESS = FULL, DIRECTORY_NAME = N'LearnFileTable')
--Other option for NON_TRANSACTED_ACCESS is READ_ONLY or OFF
GO 检查FileStream/FileTable
-- Check the Filestream/FileTable Options
SELECT DB_NAME(database_id), non_transacted_access, non_transacted_access_desc, directory_name FROM sys.database_filestream_options
WHERE DB_NAME(database_id) = 'LearnFileTable'
创建FileTable
USE LearnFileTable
GO
CREATE TABLE MyFirstFileTable AS FileTable
WITH
(
FileTable_Directory = 'MyFirstFileTable',
FileTable_Collate_Filename = database_default
);
GO 如果我们创建FileTable前没有启用FileStream,会报错
Msg 1969, Level 16, State 1, Line 1 Default FILESTREAM filegroup is not available in database '' 创建后,我们查询一下,没有记录
USE LearnFileTable SELECT * FROM [dbo].[MyFirstFileTable]
在企业管理器选择FileTable,右键 "Explorer FileTable Directory" link as shown below:
你会看到网络共享目录. 手动添加几个文件到该目录,我们返回SQLServer企业管理器看看有什么事情发生:
再运行一次查询语句
USE LearnFileTable SELECT * FROM [dbo].[MyFirstFileTable]