PHP停止在循环中两次回显数据

Question

Consider the following simple code, which should stop the same value being echoed twice

$sql = "SELECT * FROM events 
        WHERE event_date BETWEEN $curDate AND $date AND sport_type ='Rugby' 
        ORDER BY event_date ";

$lasttournament=""
echo'<select name="tournament" />';
 while($played>$venue){
   $tournament = $row['tournament'];

        if($tournament !== $lasttournament){
          $lasttournament = $tournament;
          echo'<option value="'.$tournament.'">'.$tournament.'</option>';           
         }//if 
      }//while

However my code is not giving the desired result, as you can see from image below.

Im obviously missing something, as each tournament should be displayed only once

Answer 1

Try with distinct if you need the tournament field only -

SELECT DISTINCT tournament FROM events 
    WHERE event_date BETWEEN $curDate AND $date AND sport_type ='Rugby'
    ORDER BY event_date

Or try with group by -

SELECT * FROM events 
    WHERE event_date BETWEEN $curDate AND $date AND sport_type ='Rugby'
    GROUP BY tournament 
    ORDER BY event_date

Answer 2

$sql = "SELECT DISTINCT tournament FROM events 
    WHERE event_date BETWEEN $curDate AND $date AND sport_type ='Rugby' 
    ORDER BY event_date ";

It seams you only need tournament from the sql and with this you will only get each tournament once.

Answer 3

As other replied filtering values into sql using DISTINCT or GROUP BY is the right solution, you have a cleaner code and execute less iterations.

Anyway your code wasn't working because the variable $lasttournament is overwritten every cycle with the last value so your condition work only if the same values are consecutive each other.