php操作数据库

Posted 2021-03-30 番职新鲜事

连接数据库

$link = @mysqli_connect("localhost","root","root") or die("数据连接失败");mysqli_query($link,"set names utf8") or die("设置通讯字符集错误");mysqli_query($link,"use word") or die("选择数据库失败");

查询数据全部（二维数组）：下标【index】【name】

$sql = "select *from login";$result = mysqli_query($link,$sql);$records= mysqli_fetch_all($result,MYSQLI_ASSOC);

查询单行数据（一维数组）：下标【name】

$sql ="select *from login where id=$id "; $result = mysqli_query($link,$sql); $records=mysqli_fetch_assoc($result);

增加数据

$insert="insert into goods1 values(null,'$title','$price','$inventory','$intro','$file');"

$result = mysqli_query($link,$insert);

修改数据

$update="update goods1 set title='$title',price='$price'where id=$id;"

$result = mysqli_query($link,$update);

删除数据

$sql="delete from goods1 where id=$id"; mysqli_query($link,$sql);

隐藏或显示数据（通过修改num的值查询显示隐藏）

if($num==1){

$update="update goods1 set title='$title',price='$price'where num=$num;"

$result = mysqli_query($link,$update);

$num=0;

}else{...}

语句例子：

例子1，create table students(

   id int unsigned primary key auto_increment,    name varchar(4) comment "学生姓名",    age tinyint unsigned comment "年龄",    sex char(1) comment "性别",    phone char(11) comment "手机号码",    hobby varchar(128) comment "爱好")charset utf8;

例子2，create table login( id varchar(12)  primary key ,    name varchar(4) comment "学生姓名",    num int(1) default 0 comment "是否签到")charset utf8;

例子3，create table login1( id varchar(12)  primary key ,    username varchar(8) comment "学生姓名",    password varchar(8)  comment "密码")charset utf8;

例子4，insert into login values("1713240120","李四",0)

           insert into login values("1713240121","王五",default)

           insert into login values("1713240122","陈六",1)

           insert into login1 values("1","23344","1111111")