Sql List Indexes

MySQL database sql statement commonly used optimization methods 1. Query optimization, should try to avoid full table scan, should first consider where and order by the columns involved in the establishment of the index. 2. Should be avoided in the where clause on the field null value judgment, otherwise it will cause the engine to abandon the use of indexes and full table scan, such as: select id from t where num is null You can set the default value of num 0, to ensure that Num column table does not null value ...

1.1: Increase the secondary data file from SQL SERVER 2005, the database does not default to generate NDF data files, generally have a main data file (MDF) is enough, but some large databases, because of information, and query frequently, so in order to improve the speed of query, You can store some of the records in a table or some of the tables in a different data file. Because the CPU and memory speed is much larger than the hard disk read and write speed, so you can put different data files on different physical hard drive, so that the execution of the query, ...

The logical design of database is a very broad problem. In this paper, the main key design of the table is discussed in the design of MS SQL Server, and the corresponding solutions are given. Primary key design status and problems about database table primary key design, in general, based on business requirements, based on business logic, the formation of primary key. For example, when sales to record sales, generally need two tables, one is the summary description of the sales list, records such as sales number, the total amount of a class of cases, and the other table record of each commodity ...

No database system can avoid a crash situation, even if you use a clustered, two-machine hot standby ... It is still not possible to completely eradicate the single point of failure in the system, and for most users, this expensive hardware investment cannot be sustained. So, when the system crashes, how to restore the original valuable data becomes an extremely important problem. In the recovery, the ideal situation is that your data files and log files are intact, so that only need to sp_attach_db, the data file attached to the new database, or in the downtime of the ...

No database system can avoid a crash situation, even if you use a clustered, two-machine hot standby ... It is still not possible to completely eradicate the single point of failure in the system, and for most users, this expensive hardware investment cannot be sustained. So, when the system crashes, how to restore the original valuable data becomes an extremely important problem. In the recovery, the ideal situation is that your data files and log files are intact, so only need to sp_attach_db, the data file attached to the new database, or in the downtime ...

Here is a translation of the Redis Official document "A fifteen minute introduction to Redis data Types", as the title says, The purpose of this article is to allow a beginner to have an understanding of the Redis data structure through 15 minutes of simple learning. Redis is a kind of "key/value" type data distributed NoSQL database system, characterized by high-performance, persistent storage, to adapt to high concurrent application scenarios. It started late, developed rapidly, has been many ...

Microsoft releases SQL Server RTM version March 2012 for cloud computing manufacturers can be used to describe the new focus, Yangchun, many manufacturers have released a new product on cloud computing, the strategic deployment of new products into the cloud, I have to say that the manufacturers of new cloud computing products are more like "model workers", like Microsoft in the early hours of March 1, the release of Windows 8 consumer preview, and a few days, March 7, Microsoft released the latest SQL Server 2012 new version, in addition to Microsoft to ...

After more than eight years of practice, from Taobao's collection business to today to support all of Alipay's core business, and in the annual "Double Eleven Singles Day" continue to create a world record for the transaction database peak processing capacity.

March 2012 for cloud computing manufacturers can be used to describe the release of new products, Yangchun March, many manufacturers have released a new product on cloud computing, the strategic deployment of new products into the cloud, have to say that the release of cloud computing products manufacturers are more like "model workers", Like Microsoft released the Windows 8 consumer preview in the early hours of March 1, and after a few days, March 7 Microsoft released the latest SQL Server 2012 new version, in addition to Microsoft, as well as Intel and Huawei and other manufacturers have launched a blockbuster new products. ...

Intermediary transaction SEO diagnose Taobao guest Cloud host technology Lobby database optimization is a very complex task, because it ultimately requires a good understanding of system optimization. 　　Even though the system or application system does not know much about the optimization effect is good, but if you want to optimize the effect of better, then you need to know more about it. 1, the optimization of the system to run faster the most important factor is the basic design of the database. 　　And you have to be aware of what your system is going to do, and the bottlenecks that exist. The most common system bottlenecks are as follows: ...