Excerpt from http://www.runoob.com/mysql/mysql-tutorial.html
MysqlTutorials
MySQL is the most popular relational database management system in the Web, MySQL is one of the best RDBMS (relational database Management system: relational databases Management systems) application software.
What is a database?
A database (DATABSE) is a warehouse that organizes, stores, and manages data in accordance with its data structure.
Each database has one or more different APIs for creating, accessing, managing, searching, and replicating the saved data.
We can also store the data in a file, but it is relatively slow to read the data in the file.
So now we're using a relational database management system (RDBMS) to store and manage large amounts of data. The so-called relational database is a database based on the relational model, which uses mathematical concepts and methods such as set algebra to process data in the database.
The RDBMS is the feature of the relational database management system (relational Management Systems):
- 1. The data appears in tabular form
- 2. Various record names for each behavior
- 3. Data fields corresponding to record names for each column
- 4. A number of rows and columns form a single sheet
- 5. A number of forms form database
RDBMS terminology
- Database: The database is a collection of some associated tables
- Data tables: Tables are matrices of data, and tables in a database look like a simple spreadsheet
- Columns: A column (a data element) that contains the same data, such as a postal code
- Row: a row (= tuple, or record) is a set of related data, such as a user's subscribed data
- Redundancy: Stores twice times the data, redundancy reduces performance, but improves data security
- Primary key: The primary key is unique. Only one primary key can be included in a data table. You can use the primary key to query the data
- FOREIGN key: Foreign key for associating two tables
- Composite key: Composite key (key combination) multiple columns as an index key, typically used for composite indexes
- Index: Use an index to quickly access specific information in a database table. An index is a structure that sorts the values of one or more columns in a database table, similar to a catalog of books
- Referential integrity: Referential integrity requirements are not allowed to reference entities that do not exist, and entity integrity is the integrity constraint that a relational model must meet in order to ensure data consistency
MySQL Database
MySQL is a relational database management system, is an associated database management system, the associated database to save data in different tables, rather than put all the data in a large warehouse, which increases the speed and increased flexibility.
- MySQL is open source.
- MySQL supports large databases that can handle large databases with thousands records
- MySQL uses the standard SQL data language form
- MySQL can be allowed on multiple systems and supports multiple languages, including C, C + +, Python, Java, Perl, PHP, Eiffel, Ruby, and Tcl
- MySQL is very good support for PHP, PHP is the most popular web development language
- MySQL support large database, support 50 million records of Data Warehouse, 32-bit system table file maximum support 4gb,64 bit system to support the largest table file for 8TB
- MySQL can be customized, using the GPL protocol, you can modify the source code to develop their own MySQL system
MySQL Assault (i)
