MYSQL come from?
1.MYSQL database is MYSQL AB by the Swedish R & D company, after the acquisition of ORACLE Corporation.
2.MYSQL is an open source relational database, so you can download for free
There 3.MYSQL Community Edition and Enterprise Edition
Such as how to start MYSQL?
1. Computer -> Administration -> Start MYSQL
2. Configure environment variables and user variables cmd-> net start mysql
How to turn off MYSQL?
1. Computer -> Administration -> closed MYSQL
2. Cmd->net stop mysql
How to enter into MYSQL?
Enter mysql -u + -p + username password name at the command line in any directory
How to exit MYSQL?
1. quit
2. exit
3. \q
What is a prompt?
Default string of each instruction, the default initial string is mysql>
Prompt action: prompt the user for information \ u, where the current database \ d, the current date \ D, the current server name \ h, the current port \ p, and so on.
How to use prompt prompt?
Examples: mysql> prompt \ u @ \ h \ d>
PROMPT set to ‘\u@\h \d>’
root @ localhost (none)> (user name @ server name (database name)>)
MYSQL commonly used commands
SELECT VESION (); display server version
SELECT NOW (); display the current date and time
SELECT USER (); current user is displayed;
MYSQL specification statement
Keyword function must be uppercase
Database name, table names, field names must be lowercase
SQL statements end with a semicolon
( Specification JAVA statement
Constant name in all caps.
Method names, class names, variable names follow the principle hump, but the class name first letter should be capitalized
Project name, package name all lower case, do not follow the hump principle (strict requirements)
Variable names consist of letters, numbers, underscores, $ composition, can only begin with a letter
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