Checking if database returns result in PHP

Question

I have specific issue:

if (isset($_POST['dateselected'])) {
                $selecteddate = $_POST['dateselected'];
                list($chosendate) = explode(' ', trim($selecteddate));
                $showdata = $db->prepare("SELECT * FROM adherence WHERE dateandtime= :chosendate AND lastname= :lastname");
                $showdata->bindParam(':chosendate', $chosendate);
                $showdata->bindParam(':lastname', $lastname);
                $showdata->execute();
                foreach ($showdata as $rowas){
                echo '<div class="twenty name">', $rowas["lastname"], $rowas["firstname"], '</div>';
}}

Here is my code, how to print out something, if there is no such result as requested in script? Lets say Database does not contain this kind of condition as it given in: WHERE dateandtime= :chosendate AND lastname= :lastnameHow to check returned values, and print out something if there are no correct result coming back?

I'm using rowCount() after $showdata->execute(); Value it ALLWAYS get is: -1 — JustinasT, Dec 03 '15 at 21:39
Hmm, I thought I'd used that in the past for `selects` but I guess not doc actually says `For most databases, PDOStatement::rowCount() does not return the number of rows affected by a SELECT statement.`. So guess that was a poor comment, http://stackoverflow.com/questions/6041886/how-to-get-the-number-of-rows-grouped-by-column. — chris85, Dec 03 '15 at 21:46

thepiyush13 · Accepted Answer · 2015-12-03T22:00:46.050

2

Try following:

if (isset($_POST['dateselected'])) {
            $selecteddate = $_POST['dateselected'];
            list($chosendate) = explode(' ', trim($selecteddate));
            $showdata = $db->prepare("SELECT * FROM adherence WHERE dateandtime= :chosendate AND lastname= :lastname");
            $showdata->bindParam(':chosendate', $chosendate);
            $showdata->bindParam(':lastname', $lastname);
            $showdata->execute();
            if ($rowas= $showdata->fetch(PDO::FETCH_ASSOC)) {
                do {
                    //something with data
                    echo '<div class="twenty name">', $rowas["lastname"], $rowas["firstname"], '</div>';
                } while ($rowas= $showdata->fetch());
            } else {
                echo 'no data';
            }

edited Dec 03 '15 at 22:00

answered Dec 03 '15 at 21:40

thepiyush13

1,321
1
8
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It gives "no data" when there are no results, but there are - it shows nothing. – JustinasT Dec 03 '15 at 21:46
Warning: Illegal string offset 'lastname' – JustinasT Dec 03 '15 at 21:57
it does not like line: echo '
', $rowas["lastname"], $rowas["firstname"], '
'; When information is Correct – JustinasT Dec 03 '15 at 21:59
You are my Hero :D Thanks! – JustinasT Dec 03 '15 at 22:07

score 0 · Answer 2 · answered Dec 03 '15 at 23:58

chris 85 mentioned rowcount and this is the right way. This avoid the fetch process if nothing exist. fastest method, it s made for. Also, to speed up the preprocess binding, it is better to specify what data type it is (PDO::PARAM_STR).

if (isset($_POST['dateselected'])) {
            $selecteddate = $_POST['dateselected'];
            list($chosendate) = explode(' ', trim($selecteddate));
            $showdata = $db->prepare("SELECT * FROM adherence WHERE dateandtime= :chosendate AND lastname= :lastname");
            $showdata->bindParam(':chosendate', $chosendate,PDO::PARAM_STR);
            $showdata->bindParam(':lastname', $lastname,PDO::PARAM_STR);
            $showdata->execute();
            $count= $showdata->rowCount();
            if ($count !==0){
                $rowas= $showdata->fetch(PDO::FETCH_ASSOC)
                foreach ($showdata as $rowas){
                     echo '<div class="twenty name">', $rowas["lastname"], $rowas["firstname"], '</div>';
                }}
            }else {
            echo 'no data';
            }

Ir returns error: Parse error: syntax error, unexpected 'foreach' (T_FOREACH) — JustinasT, Dec 04 '15 at 07:25

Checking if database returns result in PHP

2 Answers2