php查找mysql数据库中的所有表名

show databases;
show tables from db_name;

show columns from table_name from db_name;
show index from talbe_name [from db_name];

show status;
show variables;

show [full] processlist;
show table status [from db_name];

show grants for user;

$server = 'localhost';  
$user = 'root';  
$pass = '';  
$dbname = 'dayanmei_com';  
$conn = mysql_connect($server,$user,$pass);  
if(!$conn) die("数据库系统连接失败！");  
mysql_select_db($dbname) or die("数据库连接失败！");  
$result = mysql_query("SHOW TABLES");  
while($row = mysql_fetch_array($result))  
{  
echo $row[0]."";  
mysql_free_result($result);  

}

<?php

    //mysqli 增强-批量执行sql 语句

    //批量执行dql
    //使用mysqli的mysqli::multi_query() 一次性添加3个用户
   
    $mysqli =new MySQLi("localhost","root","root","test");
    if($mysqli->connect_error){
        die ("连接失败".$mysqli->connect_error);
    }
   
    //注意分号
    $sqls="insert into user1 (name,password,email,age) values('AAA',md5('AAA'),'AAA@hu.com',25);";
    $sqls.="insert into user1 (name,password,email,age) values('BBB',md5('BBB'),'BBB@hu.com',25);";
    $sqls.="insert into user1 (name,password,email,age) values('CCC',md5('CCC'),'CCC@hu.com',25);";
   
    //批量执行dml 可以混合使用delete insert update 最好不要使用select
    //$sqls.="update user1 set age=15 where id=1;";
    //$sqls.="delete from user1 where id=10";

    $res=$mysqli->multi_query($sqls);
   
    if(!$res){
        echo "操作失败".$mysqli->error;
    }else{
        echo "OK";
    }

?>

<?php

    //使用mysqli的mysqli::multi_query() 一次性查询表的机构和表中的内容

    //1、创建mysqli对象
    $mysqli=new MySQLi("localhost","root","root","test");
    if($mysqli->connect_error){
        die("连接失败".$mysqli->connect_error);
    }
    //2、批量查询语句
    $sqls="select *from user1;";
    $sqls.="desc user1";
    //3、处理结果
    //如果成功，至少有一个结果集
    if($res=$mysqli->multi_query($sqls)){
       
        do{
            //取出第一个结果集
            $res=$mysqli->store_result();
            while($row=$res->fetch_row()){
                foreach($row as $val){
                    echo '--'.$val;
                }
                echo '<br/>';
            }

            //及时释放内存
            $res->free();
            //判断是否还有结果集
            if($mysqli->more_results()){
                echo "********新的结果集***************<br/>";
            }else{
                break;
            }

        }while($mysqli->next_result());

    }   
    //4、关闭资源
    $mysqli->close();
?>

//判断字符串是什么编码
if ($tag === mb_convert_encoding(mb_convert_encoding($tag, "GB2312", "UTF-8"), "UTF-8", "GB2312")) {

}
else {//如果是gb2312 的就转换为utf8的
$tag = mb_convert_encoding($tag, 'UTF-8', 'GB2312');
}

/**
 +----------------------------------------------------------
 * 检查字符串是否是UTF8编码
 +----------------------------------------------------------
 * @param string $string 字符串
 +----------------------------------------------------------
 * @return Boolean
 +----------------------------------------------------------
 */
function is_utf8($string)
{
    return preg_match('%^(?:
         [x09x0Ax0Dx20-x7E]            # ASCII
       | [xC2-xDF][x80-xBF]             # non-overlong 2-byte
       |  xE0[xA0-xBF][x80-xBF]        # excluding overlongs
       | [xE1-xECxEExEF][x80-xBF]{2}  # straight 3-byte
       |  xED[x80-x9F][x80-xBF]        # excluding surrogates
       |  xF0[x90-xBF][x80-xBF]{2}     # planes 1-3
       | [xF1-xF3][x80-xBF]{3}          # planes 4-15
       |  xF4[x80-x8F][x80-xBF]{2}     # plane 16
   )*$%xs', $string);
}

function is_gb2312($str)
{
        for($i=0; $i<strlen($str); $i++) {
                $v = ord( $str[$i] );
                if( $v > 127) {
                        if( ($v >= 228) && ($v <= 233) )
                        {
                                if( ($i+2) >= (strlen($str) - 1)) return true;  // not enough

characters
                                $v1 = ord( $str[$i+1] );
                                $v2 = ord( $str[$i+2] );
                                if( ($v1 >= 128) && ($v1 <=191) && ($v2 >=128) && ($v2 <= 191) ) // utf

编码
                                        return false;
                                else
                                        return true;
                        }
                }
        }
        return true;
}

found_rows() : select
row_count() : update delete insert

drop database if exists `mytest`;
create database `mytest`;
use `mytest`;

drop table if exists `MyTestTable`;
create table `MyTestTable`(`ID` int ,`Name` varchar(10));

insert into `MyTestTable`(`ID`,`Name`)
select '1','role1' union all
select '2','role2' union all
select '3','role3';
select row_count(); -- 输出3(返回新添加的记录数),[注:如果使用insert into...values只返回1]

select * from `MyTestTable`;select found_rows(); -- 输出3(返回选择的行数)
update `MyTestTable` set `Name`='people';select row_count(); -- 输出3(返回修改的行数)
delete from `MyTestTable`;select row_count(); -- 输出3(返回删除的行数)

function mysql_modified_rows () {
        $info_str = mysql_info();
        $a_rows = mysql_affected_rows();
        ereg("Rows matched: ([0-9]*)", $info_str, $r_matched);
        return ($a_rows < 1)?($r_matched[1]?$r_matched[1]:0):$a_rows;
}