How To Set Unique Key In Sql Server 2008

Setting filter conditions to improve indexing efficiency good indexes are key to SQL Server database performance, but efficient indexes are carefully designed. As we all know, a primary key is a unique identifier for a data object, and if there is no clustered index in the datasheet, the SQL Server database will create a clustered index (Clustered index) for the primary key by default in order to maintain the uniqueness of the key. Unless the user specifically specifies that the index should be created as a nonclustered index (non-clustered index). There is no doubt that we ...

ADO. NET is the core of. NET interoperability with the database, and the Ado.net entity database enhances the ability of the. NET application to interconnect with the database, and we can easily strongly type data interoperation with the underlying database through the Ado.net Entity Data model. Greatly facilitates the design personnel, thus also enhances the database operation security. A very special problem has recently been encountered when using the domain data service to siverlight [the results in the application are not the same as the results of the database], after repeated experiments, finally found ...

With the rise of internet web2.0 websites, the relational database has become a very hot new field, the development of the non relational database products is very rapid. 　　But the traditional relational database in dealing with web2.0 website, especially the super large-scale and high concurrent SNS type web2.0 pure dynamic website already appeared to be powerless, has exposed many insurmountable problems, for example: 1, high configured--to the database higher concurrent reads and writes the demand WEB2.0 website to be based on user personalized information to generate real-time dynamic ...

First, the Hadoop project profile 1. Hadoop is what Hadoop is a distributed data storage and computing platform for large data. Author: Doug Cutting; Lucene, Nutch. Inspired by three Google papers 2. Hadoop core project HDFS: Hadoop Distributed File System Distributed File System MapReduce: Parallel Computing Framework 3. Hadoop Architecture 3.1 HDFS Architecture (1) Master ...

Intermediary transaction SEO diagnosis Taobao guest Cloud host technology Hall a strong, mature, safe, perfect products need to accumulate over the long, continuous improvement and perfect to achieve, after the development of these years, the Branch flood CMS (KESIONCMS) has grown into a safe, strong, stable and flexible Web site content Management System 　　, the stability of the platform, the perfection of product function and the expansibility of the application model and the professional aspect of the development thought are all in the leading level of the same CMS products. 2008, create the quality of CMS boutique, the flood will ...

From Wikipedia, the free encyclopediajump to:navigation, Searchapache hadoopdeveloped byapache Software RELEASE0.18.2/3 November 2008; Agowritten injavaoscross-platformt ...

The previous article is about the table storage of Azure Service, this article is mainly aimed at the other kind of special storage-binary in azure, such as unstructured storage, if our Azure services need to save non-traditional or structured data, such as pictures, audio and video media, etc. Then we need to use the BLOB storage. 　　The Windows Azure platform provides a good hosting platform and programming model. Blob storage differs from Azure table storage in terms of concept, before we see table storage being the heaviest ...

"IT168 Information" 2010 is Microsoft cloud Computing platform Construction and marketing year, Microsoft CEO Ballmer had previously said that Microsoft will "bet on the cloud computing field." 　　While security is the key to cloud computing deployment and implementation, this article hopes to share Microsoft's security strategy on cloud computing with readers by summarizing Microsoft's recent initiatives in cloud computing. The information technology industry now faces a number of challenges as it offers many opportunities for cloud computing today. According to a previous Microsoft release, a "Cloud technology architecture for Microsoft" (Securing Microsoft ...)

What is Sina app Engine Sina app Engine (SAE) is the first public cloud computing platform (http://), which was developed in-house in August 2009 and officially launched the initial alpha version on November 3, 2009. sae.sina.com.cn), SAE is the core component of Sina's cloud computing strategy. &nbs ...