From 987fb91b5231d2bcb04d81a9ad132334fc800d27 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E6=9D=8E=E5=BD=A4?= <1587475681@qq.com>
Date: Tue, 24 May 2022 19:59:48 +0800
Subject: [PATCH] ovo

---
 ...20523-php\346\223\215\344\275\234MySQL.md" | 70 +++++++++++++++++++
 1 file changed, 70 insertions(+)
 create mode 100644 "\346\235\216\345\275\244/20220523-php\346\223\215\344\275\234MySQL.md"

diff --git "a/\346\235\216\345\275\244/20220523-php\346\223\215\344\275\234MySQL.md" "b/\346\235\216\345\275\244/20220523-php\346\223\215\344\275\234MySQL.md"
new file mode 100644
index 0000000..7759173
--- /dev/null
+++ "b/\346\235\216\345\275\244/20220523-php\346\223\215\344\275\234MySQL.md"
@@ -0,0 +1,70 @@
+一、笔记
+
+（1）连接mysql服务器
+
+（2）选择数据库
+
+（3）执行sql语句：增 删 改 查等
+
+（4）处理结果集：查询语句select是有返回结果集的，通过$result,非select语句返回布尔
+
+5.关闭连接：关闭先前打开的数据库连接
+
+二、练习
+
+```mysql
+CREATE DATABASE student charset utf8;
+use student;
+CREATE TABLE user(
+id int auto_increment PRIMARY key,
+name VARCHAR(20) NOT NULL,
+score DECIMAL(10,2) NOT NULL
+);
+
+INSERT INTO user(name,score)VALUES('陈小龙','98.5'),
+('吴大虫','75.5'),
+('陈得胜','66');
+```
+
+```php
+<?php
+$add = mysqli_connect('127.0.0.1','root','123456','student')or die("失败！");
+mysqli_query($add,"set names utf8");
+$sql = "INSERT INTO user(name,score)VALUES('亮澄澄',88.5),
+('蟹不肉',100),
+('笑柄',59),
+('增猫',66)";
+$result =mysqli_query($add,$sql);
+if($result){
+    echo "添加成功！";
+}else{
+    echo"添加失败！".mysqli_error($add);
+}
+
+<?php
+$sc = mysqli_connect('127.0.0.1','root','123456','student') or die("失败！");
+$a = " delete from user where id<4";
+mysqli_query($sc,$a);
+$b =mysqli_affected_rows($sc);
+if($b==0){
+    echo"没有数据被删除！";
+}elseif ($b>0){
+    echo"删除成功！删除了{$b}条数据";
+}else{
+    die("删除失败！".mysqli_error($sc));
+}
+
+<?php
+$xg = mysqli_connect('127.0.0.1','root','123456','student')or die("失败！");
+$sql ="uptate user set name='耶' where id=4";
+$k = mysqli_query($xg,$sql);
+$num =mysqli_affected_rows($xg);
+if ($num>0){
+    echo"修改成功！";
+}elseif ($num<0){
+    echo"出错了！".mysqli_error($num);
+}else{
+    echo "内容一致，没必要修改！";
+}
+```
+
-- 
Gitee