第一章 Mysql基本概念

mysql> create table students(
-> student_id INT UNSIGNED,
-> name VARCHAR(30),
-> sex CHAR(1),
-> birth DATE,
-> PRIMARY KEY (student_id)
-> );
Query OK, 0 rows affected (0.01 sec)

mysql> desc students
-> ;
+------------+------------------+------+-----+---------+-------+
| Field      | Type             | Null | Key | Default | Extra |
+------------+------------------+------+-----+---------+-------+
| student_id | int(10) unsigned | NO   | PRI | 0       |       |
| name       | varchar(30)      | YES  |     | NULL    |       |
| sex        | char(1)          | YES  |     | NULL    |       |
| birth      | date             | YES  |     | NULL    |       |
+------------+------------------+------+-----+---------+-------+
4 rows in set (0.01 sec)

mysql> insert into students(student_id,name,sex,birth) values(41048101,'Lucy Green','1','1990-02-14');
Query OK, 1 row affected (0.01 sec)

mysql> select * from students;
+------------+------------+------+------------+
| student_id | name       | sex  | birth      |
+------------+------------+------+------------+
|   41048101 | Lucy Green | 1    | 1990-02-14 |
+------------+------------+------+------------+
1 row in set (0.00 sec)

mysql> commit;
Query OK, 0 rows affected (0.00 sec)

mysql> select name from students where student_id = 41048101;
+------------+
| name       |
+------------+
| Lucy Green |
+------------+
1 row in set (0.01 sec)

JDBC

Java Data Base Connectivity (java 数据库连接） 用于Java应用程序连接数据库的标准方法,是一种用于执行SQL语句的Java API,

可以为多种关系数据库提供统一访问,它由一组用Java语言编写的类和接口组成。

Mysql 版本:

-bash-4.1$ mysql -V
mysql  Ver 14.14 Distrib 5.6.16, for Linux (x86_64) using  EditLine wrapper

mysql> select version();
+-----------+
| version() |
+-----------+
| 5.6.16    |
+-----------+
1 row in set (0.00 sec)

1.4 Mysql 工具:
-bash-4.1$ ps -ef | grep mysql | grep -v grep | grep -v ps | grep -v bash
root       557 48793  0 Mar05 pts/9    00:00:00 su - mysql
root     48888     1  0 Mar05 pts/9    00:00:00 /bin/sh /usr/local/mysql5.6/bin/mysqld_safe --datadir=/usr/local/mysql5.6/data --pid-file=/usr/local/mysql5.6/data/dwh1.pid
mysql    49005 48888  0 Mar05 pts/9    00:00:02 /usr/local/mysql5.6/bin/mysqld --basedir=/usr/local/mysql5.6 --datadir=/usr/local/mysql5.6/data --plugin-dir=/usr/local/mysql5.6/lib/plugin --user=mysql --log-error=/usr/local/mysql5.6/data/dwh1.err --pid-file=/usr/local/mysql5.6/data/dwh1.pid

1) mysqld: SQL后台程序（即Mysql 服务器进程）。该程序必须运行之后,客户端才能连接服务器来访问数据库。

2）mysqld_safe:服务器启动脚本,在Unix 和NetWare中推荐使用mysqld_safe来启动mysqld服务器。mysqld_safe增加了

一些安全特性,例如当出现错误时重启服务器并向错误日志写入运行时间信息。