Case Statement Syntax In Oracle

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.

We want to do not only write SQL, but also to do a good performance of the SQL, the following for the author to learn, extract, and summarized part of the information to share with you! (1) Select the most efficient table name order (valid only in the Rule-based optimizer): The ORACLE parser processes the table names in the FROM clause in Right-to-left order, and the last table in the FROM clause (the underlying table driving tables) is processed first, In the case where multiple tables are included in the FROM clause, you must select the table with the least number of records as the underlying table. If...

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: ...

This paper introduces how to build a network database application method by MySQL of the golden combination of Web database, PHP is a server-side embedded hypertext Processing language similar to Microsoft ASP, it is a powerful tool to build dynamic website. While MySQL is a lightweight SQL database server that runs on a variety of platforms, including Windows NT and Linux, and has a GPL version, MySQL is considered the best product for building a database-driven dynamic Web site. PHP, MySQL, and Apache are Linux ...

R is a GNU open Source Tool, with S-language pedigree, skilled in statistical computing and statistical charting. An open source project launched by Revolution Analytics Rhadoop the R language with Hadoop, which is a good place to play R language expertise. The vast number of R language enthusiasts with powerful tools Rhadoop, can be in the field of large data, which is undoubtedly a good news for R language programmers. The author gave a detailed explanation of R language and Hadoop from a programmer's point of view. The following is the original: Preface wrote several ...

The recent investment in cloud computing by major giants has been very active, ranging from cloud platform management, massive data analysis, to a variety of emerging consumer-facing cloud platforms and cloud services. And the large-scale data processing (Bigdata 處理) technology which is represented by Hadoop makes "Business king" Change to "data is king". The prosperity of the Hadoop community is obvious. 　　More and more domestic and foreign companies are involved in the development of the Hadoop community or directly open the software that is used online. The same year with ...

The recent investment in cloud computing by major giants has been very active, ranging from cloud platform management, massive data analysis, to a variety of emerging consumer-facing cloud platforms and cloud services. And the large-scale data processing (Bigdata 處理) technology which is represented by Hadoop makes "Business king" Change to "data is king". The prosperity of the Hadoop community is obvious. More and more domestic and foreign companies are involved in the development of the Hadoop community or directly open the software that is used online. And go ...