php - Undefined index, when using mysqli_fetch_assoc, SELECT * -

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• php: “notice: undefined variable”, “notice: undefined index”, , “notice: undefined offset” 23 answers

i have simple inventory db. when trying access products table , display data in table, continually "unidentified index" , nothing have found far can assist me. starting php

conn.php

<?php $servername = "localhost"; $username = "root"; $password = ""; $database = "slfs_storesb";  // create connection $conn = new mysqli($servername, $username, $password, $database);  // check connection if ($conn->connect_errno) {     printf("connection failed: %s\n" . $conn->connect_error); }   ?> 

index.php

<?php             $sql = "select * tbl_station";             $result = mysqli_query($conn,$sql);             while($row = mysqli_fetch_assoc($result)) {                 var_dump($row);                 // print $row[4];                 //echo '<table id="t01">';                 echo $row["station_id"]." ".$row["station_name"]."  ".        $row["station_email"];                 // echo '</table>';                      }                 // } else {                    // echo "0 results";                // }             ?> 

this error

notice: undefined index: station_id in c:\wamp\www\stores\index_1.php on line 21 call stack #   time    memory  function    location 1   0.0010  246504  {main}( )   ..\index_1.php:0 gros islet fire station ( ! ) notice: undefined index: station_id in c:\wamp\www\stores\index_1.php on line 21 call stack #   time    memory  function    location 1   0.0010  246504  {main}( )   ..\index_1.php:0 gfl fire hall ( ! ) notice: undefined index: station_id in c:\wamp\www\stores\index_1.php on line 21 call stack #   time    memory  function    location 1   0.0010  246504  {main}( )   ..\index_1.php:0 headquarters ( ! ) notice: undefined index: station_id in c:\wamp\www\stores\index_1.php on line 21 call stack #   time    memory  function    location 1   0.0010  246504  {main}( )   ..\index_1.php:0 dennery class footer { footer }  

instead of using select * spell out (three) fields want access.
way query fail if 1 of fields misspelled (or doesn't exist in table).

<?php $sql = '     select         station_id, station_name, station_email             tbl_station '; $result = $conn->query($sql)     or trigger_error('query failed: '.join(',', $conn->error_list));  while( $row=$result->fetch_assoc() ) {     echo $row['station_id'], ' ', $row['station_name'],' ', $row["station_email"], "<br />\r\n"; }