PHP foreach loop unexpected behaviour

Question

What I am trying to do here is write a code to update my database automatically; for those derived attributes. Here is the part of the code where I try to grab all the rows in an array:

include("dbConnect.php");
$results = $mysqli->query("SELECT * from nw_order;");
if($results) 
    foreach($results as $hgh)
        $resultArray[] = $results->fetch_row();

else
    die("Query failed");

foreach($resultArray as $row) {
    foreach($row as $field)
        print $field." ";
    print "<br>";
}

The foreach grab only even numbered rows for some reason. Also, trying to substitute foreach with while gives me memory shortage error. I am so tired I will check in tomorrow. If you can help me out that will be awesome.

Why do you loop through the $results variable to fill up the $resultArray variable to loop through it again? — Andrew Coder
– Andrew Coder, Commented Jan 14, 2016 at 19:15
that's NOT how you fetch rows from a result. the foreach() grabs one row, then you simply throw away $hgh and fetch ANOTHER row with the fetch_row() call. if you insiste on foreach, then at least change it to foreach(...) { $resultArray[] = $hgh; } — Marc B
– Marc B, Commented Jan 14, 2016 at 19:16

bloodstix · Accepted Answer · 2016-01-14 20:37:56Z

1

include("dbConnect.php");
$results = $mysqli->query("SELECT * from nw_order;");
$rows = array();
if($results) {
  $rows = $results->fetch_all();
}

foreach($rows as $row) {
  foreach($row as $field) {
        echo $field." ";
  }
  echo "<br>";
}

But actually I'd rather neither "SELECT * " nor print all fields regardlessly. I find things more maintainable when they are more explicit.

edited Jan 14, 2016 at 20:37

bloodstix

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answered Jan 14, 2016 at 19:18

Max

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4 Comments

bloodstix Over a year ago

I'd suggest that if you clean/improve his code, do it completely. One should use brackets for every conditional or loop statement. Someday someone else mantains this code and in a hurry adds another line to the if($results)-block and wonders why its not working. And another post like this will be born :).

Max Over a year ago

:D yes these posts keep being born all the time

Lian Diktea Over a year ago

Ok. Thank you. This looks nice

Lian Diktea Over a year ago

By the way, can you explain why using while($results) causes memory shortage?

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