UC知道sql语句连接查询
来源：百度知道 编辑：UC知道 时间：2024/06/30 07:41:56
用户信息表 information 字段 username，email，phone；发言记录表 msg 字段：id，sender；sender=username查询用户的username，email，phone按id顺序显示
$sender=$_SESSION['name'];
$connect=mysql_connect("$databaseserver","$user","$password")or die("Unable to connect!");
mysql_select_db($databasename)or die("Unable to select database!");
$select="select username,phone,email from information where username='$sender'";
$result=@mysql_query($select);
if($myrow=@mysql_fetch_array($result))
{
$sender=$myrow["username"];
$phone=$myrow["phone"];
$email=$myrow["email"];
echo $sender."<br>".$phone."<br>".$email;
}
这样一个表查询可以输出，按照你们的方法查询两个表就不能输出
select 发言记录 from table_name where 用户名='XXX' order by 发言记录
--------------------------------------------------------------------
select a.username,a.email,a.phone from information a,msg b where a.username=b.sender and a.username='XXX' order by b.id
-----------------------补充----------------
输出不了是因为你少写条件了
a.username=b.sender 这个你没写，所以结果当然输出不了
select username,email,phone form information a,msg b
where a.username = b.sender
order by b.id
--or
select username,email,phone form information a,msg b
where a.username = b.sender
and a.username = 'XXX'
order by b.id
你表结构都没说。。。怎么写呢?
简单一点的：
user表(user)：user_id,user_name
发言表(speaklist):list_id,user_id,content,date
sql语句：select list_id,user_name,content,date
from user,speaklist
where user_id=要查的用户id and userid.userid=speaklist.userid
order by list_id asc
理解意思了 可以参