node (four)

MySql installation

MySQL is a way to store data, but also data persistence saved
    persistently saved There are many solutions: database ... and so
on cache Question: server and client
    server is a database
    client has a cookie and some, but customers end relatively not very safe, but also to see what the specific needs
windows install MySQL:
    to download the installation package, note the version 5. * version on the line, .msi suffix (that is, the installation package), and finally it is the environment variables!
    generally using the integrated environment on the line, I now use is: https://www.xp.cn/ phpStudy, then you can start MySQL;

---

MySql operation

Use the command line 1. 2. 3 graphical user codes operation 
command line: Note semicolon; 
{ 
    DDL the DML the DCL DTL; 
        DDL: The operation of the database, create a database, creating tables, delete tables, databases are deleted DDL 
        DML (emphasis): operating data, add, delete, change, 
        DCL: permissions 
        DTL: transactional operations 
} 
{ 
    graphical user: 
        { 
            software: navicat 
            download and install tutorial addresses (hack): HTTP: // www.downcc. COM / Soft / 322714.html 
        } 
        {
             1. database link -> provided state database is open, phpStudy in the MySQL (run) may be used; 
                New link: a connection name, host, port, user name, password, 
                    the connection name: display name 
                    host: localhost 
                    port: 3306 (default)
                    Username: root (default) 
                    Password: password to view phpstudy in MySQL 
                connection is successful, see a lot of tables, there is a default MySQL table, under normal circumstances do not recommend changes to 
                    these tables excel spreadsheet and also as 
                    general cases, for a project there is a database, a database and then there are more tables 
                we can create some tables and databases (right) in the software inside
             2 New database. 
                right New: database name, character set, collation 
                    database name: node_js (nickname) 
                    character set : utf8 
                    collation: utf8_general_ci (support Chinese encoding)
             3 . Create the table 
                in just a database, right-New table
                     1 field: that is, the horizontal axis those content 
                        name, type, length, decimal point is not null (not empty), key (automatic growth)  
                    unique identifier: every table needs to have one, that is, to distinguish the meaning of (id)
                        because the data is no unity, there will be the same such as name, password, also have the same 
                    type:
                        int : range: 0 ... 
                        concerning the type of it, moderate on the line, the maximum and minimum difference is performance issues, space 
                fields: id, type, length, decimal point is not null, the key 
                    the above mentioned id int 11 0 to true (√) primary key (automatic growth) 
                    username VARCHAR 50 
                    Age int 11 
                    Sex tinyint 1 (Note: male: 1 female: 0 ) 
                    save: the Users 
        } 
}