Composite Key Database

Designing 1 applications doesn't seem to be difficult, but it's not easy to achieve the optimal performance of the system. There are many choices in development tools, database design, application structure, query design, interface selection, and so on, depending on the specific application requirements and the skills of the development team. This article takes SQL Server as an example, discusses the application performance optimization techniques from the perspective of the background database, and gives some useful suggestions. 1 database design to achieve optimal performance in a good SQL Server scenario, the key is to have 1 ...

Cloud computing, things networking, mobile internet is a popular word in recent years, and these new concepts are emerging, a large number of semi-structured, unstructured data is growing rapidly, pictures, audio videos, social networks and other content filled with the lives of each user. There is no doubt that the era of big data is really coming. 　　According to IDC, global data will reach 10 trillion TB in 2015, and the annual composite growth rate will reach 38% in 2020, while the length of usable storage capacity is expected to be 28%. The ability to control large data can help companies find the best model to support the business ...

The document database of NoSQL database technical characteristics Today's cloud computing practitioners are not unfamiliar with the term nosql, though many technicians have long been working on relational databases, but now they are looking forward to nosql technology. The transition from relational to NoSQL databases is definitely a big change to be considered for businesses. This involves not only the changes in software, but also the conceptual changes in data storage. Most non-relational databases have fast and scalable features. By discarding relational storage models and schemas, relationships ...

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 ...

1, use the index to traverse the table faster. The index created by default is a non-clustered index, but sometimes it is not optimal. Under non-clustered indexes, the data is physically stored on the data page. Reasonable index design should be based on the analysis and prediction of various inquiries. In general: a. There are a large number of duplicate values, and often range query (>, <,> =, <=) and order by, group by occurred columns, consider the establishment of cluster index; Column, and each column contains duplicate values ​​can be ...

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 ...

Founded in 2008, Vpon is a mobile advertising company whose main business is to accept advertisers to post ads on mobile apps launched by its partners. Last month, Vpon launched a system advertising analysis system called 3S (Sales supporting system), a large data mining, analysis and processing system built on the Hadoop platform. The most important function of this system is to be able to accurately statistic and analyze the time, place and various preferences of the user click Mobile Application, so as to help advertisers to make more effective advertising.

"Guide" the author (Xu Peng) to see Spark source of time is not long, note the original intention is just to not forget later. In the process of reading the source code is a very simple mode of thinking, is to strive to find a major thread through the overall situation. In my opinion, the clue in Spark is that if the data is processed in a distributed computing environment, it is efficient and reliable. After a certain understanding of the internal implementation of spark, of course, I hope to apply it to practical engineering practice, this time will face many new challenges, such as the selection of which as a data warehouse, HB ...

According to IDC, global data will reach 10 trillion TB in 2015, and the annual composite growth rate will reach 38% in 2020. Due to the lower cost of data, the rapid increase of data volume, coupled with the emergence of new data sources and data technology has evolved a variety of data types. Big data is waving at us. With large data, large data analysis and proper management will have a great impact on the enterprise data center. 　　As the world's largest database software company, Oracle is in time to launch a number of technology products for large data to meet the needs of enterprises and enhance their own value. ...

Recently busy graduate design, the need for document translation. I thought that before the translation of a poor, but always feel not rigorous enough. My graduation project is mainly to help the teacher's institute to be a website, already have a website, but the teacher and I think the old version of the site is very old. So volunteered. The site needs to be refactored, and the Natural Information Architecture section is an important part of it, though it has also been seen quite a bit before, such as "thinking of the OR search in the kitchen" is a sign of thought, but systematically translating the Five Simple Steps team Works of "A Practical G ...