Types Of Indexes In Sql With Examples

The greatest fascination with large data is the new business value that comes from technical analysis and excavation. SQL on Hadoop is a critical direction. CSDN Cloud specifically invited Liang to write this article, to the 7 of the latest technology to do in-depth elaboration. The article is longer, but I believe there must be a harvest. December 5, 2013-6th, "application-driven architecture and technology" as the theme of the seventh session of China Large Data technology conference (DA data Marvell Conference 2013,BDTC 2013) before the meeting, ...

April 24, we released a preview version of the SQL Database base level (preview) and standard (preview) new service levels and new business continuity features. In this blog post, we delve into the performance of new levels in SQL Database. Begin with the need for change. We focus on performance (specifically predictable performance) in new service levels, driven primarily by strong customer feedback on SQL Database Web-Level and enterprise-class performance. Web-and enterprise-level performance ...

A good database product is not equal to have a good application system, if can not design a reasonable database model, not only will increase the client and Server section program programming and maintenance of the difficulty, and will affect the actual performance of the system. Generally speaking, in an MIS system analysis, design, test and trial run stage, because the data quantity is small, designers and testers often only notice the realization of the function, but it is difficult to notice the weak performance, until the system put into actual operation for some time, only to find that the performance of the system is decreasing, At this point to consider improving the performance of the system will cost more ...

Type selection and design of bigtable NoSQL database release time: 2012.04.16 14:20 Source: Blog Author: Blog This paper introduces the selection strategy and schema design principle of Bigtable/hbase type NoSQL database system. Data scale BigTable Class database system (Hbase,cassandra, etc.) is to solve ...

Content Summary: The data disaster tolerance problem is the government, the enterprise and so on in the informationization construction process to be confronted with the important theory and the practical significance research topic. In order to realize the disaster tolerance, it is necessary to design and research the disaster-tolerant related technology, the requirement analysis of business system, the overall scheme design and system realization of disaster tolerance. 　　Based on the current situation of Xinjiang National Tax Service and the target of future disaster tolerance construction, this paper expounds the concept and technical essentials of disaster tolerance, focuses on the analysis of the business data processing of Xinjiang national tax, puts forward the concrete disaster-tolerant solution, and gives the test example. Key words: ...

First, the importance of the index The index is used to quickly find a column in a particular value of the line. Instead of using an index, MySQL must start with the first record and then read the entire table until it finds the relevant row. The larger the table, the more time it takes. If the table in the query column index, MySQL can quickly reach a location to search the middle of the data file, there is no need to see all the data. Note that if you need to access most of the rows, sequential reads are much faster since we avoid disk searches. If you use Xinhua Dictionary to find "Zhang" the Chinese characters, do not use the directory, then ...

With the start of Apache Hadoop, the primary issue facing the growth of cloud customers is how to choose the right hardware for their new Hadoop cluster. Although Hadoop is designed to run on industry-standard hardware, it is as easy to come up with an ideal cluster configuration that does not want to provide a list of hardware specifications. Choosing the hardware to provide the best balance of performance and economy for a given load is the need to test and verify its effectiveness. (For example, IO dense ...