diff --git "a/\351\237\246\346\260\270\351\237\254/20220523-php\346\223\215\344\275\234mysql.md" "b/\351\237\246\346\260\270\351\237\254/20220523-php\346\223\215\344\275\234mysql.md" new file mode 100644 index 0000000000000000000000000000000000000000..dcb113d5fdc9377bf0e00ca8a84a92975a8c0171 --- /dev/null +++ "b/\351\237\246\346\260\270\351\237\254/20220523-php\346\223\215\344\275\234mysql.md" @@ -0,0 +1,106 @@ +![2022-5-23 10-41-39](https://tva1.sinaimg.cn/large/e6c9d24egy1h2ib4qh0bgj218g0p0mzw.jpg) + +```mysql +CREATE DATABASE student CHARSET utf8; +use student; +CREATE TABLE user( +id int NOT NULL primary key auto_increment, +name VARCHAR(20) NOT NULL, +score DECIMAL(10,2) NOT NULL +); +INSERT INTO user(name,score) VALUES ('陈小龙',98.5); +INSERT INTO user(name,score) VALUES ('吴大虫',75.5); +INSERT INTO user(name,score) VALUES ('陈得胜',66); +``` + +```php +"; +}else{ + echo "添加失败"."
"; +} + +$delete="delete from user where id>5"; +$c=mysqli_query($a,$delete); +$cc=mysqli_affected_rows($a); +if ($cc==0){ + echo "没有相应数据,删除失败"."
"; +}else if($cc<0){ + die("运行错误"."
"); +}else{ + echo "删除成功"."
"; +} + +$update="update user set name='李白' where id=2"; +$d=mysqli_query($a,$update); +if ($update){ + echo "修改成功"."
"; +}else{ + echo "修改失败"."
"; +} + +$select="select * from user"; +$d=mysqli_query($a,$select); + +$e=mysqli_fetch_all($d); +foreach ($e as $ee){ + foreach ($ee as $eee){ + echo $eee." "; + } + echo "
"; +} + +while ($f=mysqli_fetch_assoc($d)){ + echo $f['id']."=".$f['name']."=".$f['score']."
"; +} + + +``` + +```php +/* + +pdo扩展 可以接所有以支持的数据库 +未知时var_dump(); +mysqli_connect_error(); 错误输出 +die(); + +直接连接服务器同时选择好数据库 +mysqli_connect(host,username,password,dbname,port,socket); +mysqli_connect(服务器地址,用户名,密码,数据库名,端口号); +可选,规定主机名或ip地址 +规定mysql用户名 +规定mysql密码 +规定默认使用的数据库 +规定socket或要使用的已命名pipe + +先连接服务器再选择数据库 +mysqli_connect(host,username,password); +mysqli_select_db(); + +增,删,改,查 +mysqli_query(连接对象,mysql语句); +插入数据 insert into 表名(字段,字段……)values(),()……; +删除数据 delete from 表名 where 条件; +修改数据 update 表名 set 字段='修改内容',…… where 条件; +查询 select 字段 from 表名 where 条件; + +mysqli_fetch_all(); 返回一个二维数组 +mysqli_fetch_array(); 从结果集中以数组形式返回一行,这个数组是索引和关了数组的结合体 +mysqli_fetch_assoc(); 从结果集中以关联数组形式返回一行,每次会自动下移一行 +mysqli_fetch_row(); 从结果集中以索引数组形式返回一行,每次会自动下移一行 + + + */ +``` +