PHP如何按日期查询

MYSQL里字段addtime为时间戳
我现在须要这样查询
xx.php?u=20130328&page=1 &page=这个用来分页
 这样查询20130328或20130329这一天数据

<?phpinclude "../include/song.inc.php";$key = $_GET['u'];if($_GET["page"]){    $page=$_GET["page"];#获取要显示的页码}else{    $page=1;#没有参数传入时，显示第一页}$col=20;#每页显示记录条数$p=($page-1)*$col;$runSql = mysql_query("select * from cmsdj_song where uid = '$key' order by id desc limit ".$p.",".$col."");while($row = mysql_fetch_array($runSql)){//下面这些是调用值$sid=$row['id'];$suid=$row['uid'];$supip=$row['upip'];$name=$row['name'];$sname=substr($name,0,30);$sfile=$row['file'];$surl=$row['url'];$swjdx=$row['wjdx'];$stime=date('Y-m-d H:i:s',$row['addtime']);//$b64file=base64_encode($surl);?><table width='100%' border='0' cellpadding='0' cellspacing='0' class='tb_style'><tr><center><td width='5%' height='20' class='td_border'> <? echo $sid;?></td><td width='25%' class='td_border'><a href='u.php?i=<? echo $sfile;?>'> <? echo $sname;?></a></td><td width='20%' class='td_border'><a href='u.php?i=<? echo $sfile;?>'><? echo $sfile;?></a></td><td width='20%' class='td_border'><a href='u.php?i=<? echo $sfile;?>'><? echo $surl;?></a></td><td width='5%' class='td_border' align='center'><? echo $swjdx;?></td><td width='10%' class='td_border' align='center'><? echo $supip;?></td><td width='12%' class='td_border' align='center'><? echo $stime;?></td><td width='3%' class='td_border' align='center'><a href='del.php?id=<? echo $sid;?>'><img  src='/img/no.gif' border='0' alt="PHP如何按日期查询" ></a></td></tr></center></table><?php}?>     <?php$col=20;#每页显示记录条数$count=mysql_query("select id from cmsdj_song where uid like '%$key%'");#取得记录总条数$num = mysql_num_rows($count)/$col;#计算页数$nnx = mysql_num_rows($count);#计算页数$num=ceil($num);#无条件小数进位确定总页数mysql_close();?>

回复讨论(解决方案)

FROM_UNIXTIME()  UNIX时间戳转换为日期
UNIX_TIMESTAMP() 日期转换为UNIX时间戳 

$u = $_GET['u'];$starttime = strtotime($u.'000000');$endtime =  strtotime($u.'235959');$runSql = mysql_query("select * from cmsdj_song where addtime > '$starttime' and addtime<'$endtime' order by id desc limit ".$p.",".$col."");