php对Mysql的增删改查
1,添加数据
function insertData($sql){
#连接数据库
$mysqli=new mysqli("localhost","root","数据库密码","tom");
if($mysqli->connect_errno){
die($mysqli->connect_errno);
}
//向tom数据库中的think_data表插入数据
$result=$mysqli->query($sql);
if($result){
echo '插入成功';
}else{
echo '插入失败';
}
$mysqli->close();
}
$insert_sql="insert into think_data values ('6','如来','18')";
insertData($insert_sql);
2,更新数据
function updateData($sql){
#连接数据库
$mysqli=new mysqli("localhost","root","数据库密码","tom");
if($mysqli->connect_errno){
die($mysqli->connect_errno);
}
$result=$mysqli->query($sql);
if($sql){
echo "更新数据成功!";
}else{
echo "更新数据失败!";
}
$mysqli->close();
}
//把think_data表中id=6的这一行中的name改为太上老君
$update_sql="update think_data set name='太上老君' where id=6";
updateData($update_sql);
3,删除数据
function deleteData($sql){
$mysqli=new mysqli("localhost","root","数据库密码","tom");
if($mysqli->connect_errno){
die($mysqli->connect_errno);
}
$result=$mysqli->query($sql);
if($sql){
echo "删除数据成功!";
}else{
echo "删除数据失败!";
}
$mysqli->close();
}
//删除id等于6的这一行
$delete_sql="delete from think_data where id=6";
deleteData($delete_sql);
3,查询数据的两种方法
<?php
//查询数据的三种方式
function fetchDataone($sql){
$mysqli=new mysqli("localhost","root","数据库密码","tom");
if($mysqli->connect_errno){
die($mysqli->connect_errno);
}
$result=$mysqli->query($sql);
//var_dump($result);
#查询数据的第一种方法,返回数组格式
if($result->num_rows){
//$row=$result->fetch_row();
//print_r($row);
while($row=$result->fetch_row()){
print_r($row);
}
}
$mysqli->close();
}
//查询think_data这表的数据库
$fetch_sqlone="select * from think_data";
fetchDataone($fetch_sqlone);
//查询数据的第二种方式,返回json数据格式
function fetchDatatow($sql){
$mysqli=new mysqli("localhost","root","数据库密码","tom");
if($mysqli->connect_errno){
die($mysqli->connect_errno);
}
$result=$mysqli->query($sql);
//第二种方法,返回json数据格式
$row=$result->fetch_all(MYSQLI_ASSOC);
echo json_encode($row);
$mysqli->close();
}
//查询think_data这表的数据库
$fetch_sqltow="select * from think_data";
fetchDatatow($fetch_sqltow);