33 or acquaintance database and a simple command

    First, the database concepts

  1. random saved to a file in the data format is vastly different 

2. Software development directory specification
defines the location data stored
ps: data are stored locally

3. Save the data portion of the deposit to a public place all users of the data must be related to the common areas to check

two, mysql database of
  
   Is essentially a web-based application to communicate 
any underlying network-based communications software are socket

server
- based socket communication
- sending and receiving messages
-SQL statement (a common standard)
client
- based socket communication
- send and receive messages
-SQL statement

ps: MySQL not only supports MySQL client to operate also support other programming languages directly manipulate
python java c ++ php syntax is not the same

three, DBMS: database management system
    
Relational databases 
    can be linked and limitations of data between the data and the 
        relational database usually table structure, which means you're in a relational database 
        first step is to determine the structure of table 

        fields have a specific type of 
            memory with a name string 
            stored password with the number 
            stored with the date of birth 

    MySQL, oracle, sqlite, db2, sql server 
 non-relational databases 
    often store data in the form of k, v keys 
    non redis, mongodb (document database very close relationship type relational data), memcache 
 MySQL can actually see it as a support for remote file operations software 

 library    >>>    folder 
 list    >>>    file 
 records >>>    data in the file line by line, called a section of the recording 


 header is table the first row of data 
 field names field + field type

 


Fourth, the installation database
Do not in the IT industry to try the latest version of the software 

after downloading is the MySQL server and client download down 
    decompression 
    view the file directory 

    server 
        mysqld 

    client 
        mysql 

    to start mysqld
         1 . Switch to the bin directory
         2 Executive mysqld 
    PS : make early MySQL configuration when the terminal is recommended that you run as administrator 

    Windows + r to start an ordinary user 

    mysql landing at the time of the initial password is not directly enter 

    the mysql sql statement is not the end of the semicolon semicolon default knock you completely did not enter 
    the client will let you continue typing

Fifth, the client landing

  

The client landed
         MySQL -h 127.0.0.1 -P-uroot-3306 - the p- 
        can be abbreviated MySQL
         -uroot-- the p-

 
        If you do not enter a user name and password by default is landed guest mode function can be used in very few 

    clients logout 
        Exit; 
        quit; 
    View all databases 
        show databases; 


    view a process 
        tasklist | findstr name 

    to kill the process 
        taskkill / F PID process ID /

Sixth, the production environment variable

  

The startup files are located in the path environment variable added to the system's 
    Note: After configuring a while to restart the mysql server and cmd terminal 

will be made into a system service mysqld 
    production system services your administrator cmd terminal must be a mysqld

     - install
 
start services command services.msc 
change passwords 
    without a password mysqladmin
    

         -uroot--p password 123 
    under have a password mysqladmin
         -uroot--p123 password 123456 

    when the command input error can be used when \ c cancel the previous command cancel

decryption

  

Now stopped has started the server

     1 . Username and password to skip verification of the server function is activated 
        mysqld --skip-grant- Tables start the server authorization skip Table
     2 . Modify the administrator password corresponding to the user 
        update mysql.user password SET = password (123) WHERE user = ' the root '  and Host = ' localhost ' ;
     . 3 . Close this manner the server to re-authenticate the username and password to start
     4. in the normal manner username and password server connected mysql

Profiles

\ s View mysql server simple configuration 
    suffix configuration files usually are ini the end of the 

    mysql configuration file that comes not to modify 
    , but you can create a configuration file my.ini 
    mysql server will automatically load your my start. ini configuration in the configuration file 

    need to first stop the server restart to take effect after you finish modifying the configuration file 

    to modify the configuration file must restart the server

 

Seven basic database operations

Library similar to folders
  
By 
            create database db1; 
        investigation 
            show databases; check all 
            show create database db1; search a single table 
        change 
            ALTER Database DB1 charset = ' GBK ' ; modified encoding 
        puncturing 
            drop database db1; deletion library

Table        similar to the file name

  

You need to be specified when creating a table of library 
            specify the library: use library name 
            to view the current location of the library: select database () 

        by 
            create table userinfo (id int, name char); 

        check 
            show tables; View all of a library table below 
            show create table userinfo; Display contents inside 
            desc UserInfo;     <==> DESCRIBE UserInfo; Display header 
        change 
            ALTER Modify table UserInfo name char ( 32 ); 
        puncturing 
            drop table userinfo;

recording

Create to a library or specify an existing library 
        switch to this library to create the table 
        and then the operation record 
        create database db1; Create Library 
        Create Table UserInfo (ID int, name char ( 32 ), password int); create the tables and fields 

        increase 
            iNSERT INTO UserInfo values ( . 1, ' Jason ' , 123 ); inserting a single data 
            iNSERT INTO UserInfo values ( . 1, ' Jason ' , 123), 
(2, ' Egon ' , 123), (. 3, ' Tank ' , 123 ) ; inserting a plurality of data check SELECT * fromUserInfo; field information of all query SELECT name from UserInfo; field information query specifies SELECT ID, name from UserInfo ID = WHERE. 1 or name = 'Tank'; information field with filter conditions change Update UserInfo SET name = ' Kevin ' WHERE =. 1 ID ; a modified data information field Update UserInfo SET name = ' Jason ' , password = 666. 1 = WHERE ID ; a plurality of data fields modify delete Delete from UserInfo. 1 WHERE = ID ; qualified data specified delete Delete from userinfo; will delete all data in the table

 

  

 


 

 

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Origin www.cnblogs.com/wukai66/p/11374207.html