How To View Index In Mysql

mysql tutorial to modify the table / field to add / delete table index create table test (blob_col blob, index (blob_col (10))); In mysql 5.1, myisam and innodb table prefix can reach 1000 bytes long. Note that the prefix limit should be measured in bytes, while the prefix length in the create table statement is interpreted as the number of characters. Must be considered when specifying the prefix length for columns that use multi-byte character sets. ...

As the most popular open source database, MySQL is widely used in Web applications and other small and medium-sized projects. However, in many large IT companies, MySQL has gradually deviated from the original open source version after being highly optimized and customized, more like a branch, such as the Webscalesql of Facebook, which was not long ago open source. 　　Recently, Mr. Xiong has published a blog post, from the perspective of large-scale web site architecture development of the changes in MySQL application, here for you to share. This article mainly describes the different and ...

History of the most complete MySQL backup method, you need friends can refer to the next. I have used the backup methods are: mysqldump, mysqlhotcopy, BACKUP TABLE, SELECT INTO OUTFILE, or backup binary log (binlog), can also be directly copied data files and related configuration files. MyISAM table is saved as a file, it is relatively easy to back up, several methods mentioned above can be used. Innodb all the tables are ...

The following article is mainly about the specific method of implementing a simple and practical optimization of the MySQL database, as well as what specific steps in the actual operation are worthy of our attention. The following article describes the MySQL database is a simple practical optimization of the specific methods to achieve, including how to conduct regular table analysis and inspection, and how to properly optimize the table on a regular basis, the following is a description of the specific program, I hope in your future Learning will be helpful. 1, regular analysis table and checklist analysis table syntax is as follows: ANAL ...

If a computer manufacturer, its database holds machine and accessories product information. The table used to save the whole product information is called pc; the table used to save the parts supply information is called parts. There is a field in the pc table, used to describe the type of CPU used in this computer; there is a field in the parts table, the description of the CPU model, we can think of it as a list of all CPU models. Obviously, the CPU used by this manufacturer must be a model that exists in the supply information sheet. At this time, two tables ...

Usually speaking of foreign keys, we only mention "the purpose of the foreign key is to determine the referential integrity of the data." However, what foreign keys specifically include the actions and meanings? 1, set the outer chain: (1), create a foreign key through create table: see 2 lines of code is built in the table command: create table city (... key idx_fk_country_id (country_id), constrain ...

Overview 2.1.1 Why a Workflow Dispatching System A complete data analysis system is usually composed of a large number of task units: shell scripts, java programs, mapreduce programs, hive scripts, etc. There is a time-dependent contextual dependency between task units In order to organize such a complex execution plan well, a workflow scheduling system is needed to schedule execution; for example, we might have a requirement that a business system produce 20G raw data a day and we process it every day, Processing steps are as follows: ...

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, ...

Overview How to deal with high concurrency, large traffic? How to ensure data security and database throughput? How do I make data table changes under massive data? Doubanfs and DOUBANDB characteristics and technology implementation? During the QConBeijing2009, the Infoq Chinese station was fortunate enough to interview Hong Qiangning and discuss related topics. Personal Profile Hong Qiangning, graduated from Tsinghua University in 2002, is currently the chief architect of Beijing Watercress Interactive Technology Co., Ltd. Hong Qiangning and his technical team are committed to using technology to improve people's culture and quality of life ...

Affirmation: The article is longer, if you are the industry webmaster please read carefully, welcome to join the industry webmaster QQ Group: 37466050 (using the invitation mechanism, add please specify the URL.) The rise of the industry web site has become an unstoppable trend in China's e-commerce development, according to a survey of 07 growth rate is expected to be close to 50%. For many industry websites, after a period of development, to seize the opportunity to win a certain market share. 　　At the same time, will face many new challenges, the market competition will become more and more fierce. Compared with the Internet companies that have VC support ...