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show databases;                 显示数据库
create database DataBaseName;    创建数据库
drop databases 数据库名         删除数据库
drop table 表名                 删除表
use databaseName;               进入相应的数据库
show tables;                     查看当前数据库中有的表
MySQL中部分数据类型(dateType):
integer 整型
varchar(Number)   Number可以是任意整数
text 文本类型,可以存大量文本
float 浮点型
date 日期型
创建表
create table tableName(
     columnName    dataType,
       ……………..
columnName    dataType
primary key(‘ID’);设置ID为主键
Not null auto_increment, 可以通过AUTO_INCREMENT属性为新的行产生唯一的标识:
例如:CREATE TABLE xxx (
    id integer NOT NULL AUTO_INCREMENT,
    name CHAR(30) NOT NULL,
PRIMARY KEY (id)
);

增:insert into tableName values(value,value,value……);                  向tableName中插入信息
查:select * from tableName;                 查看当前表中的所有数据
删delete from tableName where 条件;             删除数据库中的数据
改update tableName set 条件;                 修改数据库中的数据

mysql基本的步骤:
(1)             mysql_connect(“localhost”,”root”,”密码”)||die(“连接数据库服务器失败”);
(2)             mysql_select_db(“数据库名”)||die(“连接数据库”);
(3)             $strsql=”(在Phpmyadmin中编辑)”;发送sql语句
(4)             mysql_query(“set names ‘gb2312’ ”);防止出现乱码
(5)             $res=mysql_query($strsql)接收SQL语句
(6)             Mysql_colse(); 结束

$a=Mysql_fetch_row();
描述
检索结果集的下一行。在mysql_store_result()之后使用时,如果没有要检索的行,mysql_fetch_row()返回NULL。在mysql_use_result()之后使用时,如果没有要检索的行或出现了错误,mysql_fetch_row()返回NULL。
行内值的数目由mysql_num_fields(result)给出。如果行中保存了调用mysql_fetch_row()返回的值,将按照row[0]到row[mysql_num_fields(result)-1],访问这些值的指针。行中的NULL值由NULL指针指明。
可以通过调用mysql_fetch_lengths()来获得行中字段值的长度。对于空字段以及包含NULL的字段,长度为0。通过检查字段值的指针,能够区分它们。如果指针为NULL,字段为NULL,否则字段为空。
返回值
下一行的MYSQL_ROW结构。如果没有更多要检索的行或出现了错误,返回NULL
$b=mysql_num_rows();
描述
返回结果集中的行数。
mysql_num_rows()的使用取决于是否采用了mysql_store_result()或mysql_use_result()来返回结果集。如果使用了mysql_store_result(),可以立刻调用mysql_num_rows()。如果使用了mysql_use_result(),mysql_num_rows()不返回正确的值,直至检索了结果集中的所有行为止。
返回值
结果集中的行数

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