如何为给定任务使用while条件？

i am fetching user details using date

if(date("d")==1) {
    $time  = "m";
}
if(date("l")=="Friday") {
    $time  = "w";
}
$time  = "d";

$sql=mysql_query("select user from table_users where $reprt=".$time .");
while($row=mysql_fetch_Array($sql) {
    $sql==mysql_query("select * from table_register where $user="$row[0]");
}

here when (date("d")==1) i want to select statement using both d and m how is that possible.

Let's see if I got this right... you should should be doing this only in one query if I understand properly

select * from table_register where $user in (select user from table_users where $reprt=".$time)

would be a much better query then what you have set up... still not the best but at least it's only 1 query.

to the actual question, you should just change your code to the following

if(date("d")==1)
{
 $time  = "m";
}
if(date("l")=="Friday")
{
 $time  = "w";
}

if($time == "m") // this is when you want to also search for d right?
{
  //we do what I suggested earlier with a slight change
  mysql_query("select * from table_register where $user in (select user from table_users where  $reprt=".$time." OR $reprt=d)");
}
else
{
  //we do what I suggested earlier
  mysql_query("select * from table_register where $user in (select user from table_users where  $reprt=".$time.")");
}

Hope this helps.

let's say you have a String. name it S. you also have a string query = "select * from table_register where "

what you have to do is

 query = "select * from table_register where "  
  if(date("d")==1){
           s = "$report_frequency  = \"m\" OR $report_frequency  = \"d\" ";
    }
    elseif(date("l")=="Friday"){
         s = "$report_frequency  = \"m\" ";
    }
    else{
    s = "$report_frequency  = \"d\" ";
    }

    query = query.s;

    $sql=mysql_query(query);
    ...

In other word, construct your query string dynamically using Strings

In your code you're using $time = "d"; outside the IFs, so you'll always have $time=d, so replace the code with this:

if(date("d")==1){
  $time  = "m or $reprt='d'";
}
if(date("l")=="Friday"){
  $time  = "w";
}

$sql=mysql_query("select user from table_users where $reprt=".$time);
while($row=mysql_fetch_Array($sql){
  $sql=mysql_query("select * from table_register where $user='$row[0]'");
}