sql语句不返回任何结果

Question

Hi I am creating some dummy data in a sql statement and returning the data in a jso n format. I believe I am connecting to the mysql db ok through odbc. However the dataset appears to be empty when I run the same query in workbench it returns data ok.

This is how the data is returned to the webpage making the call

"[{"coords":{"lat":null,"lng":null},"iconImage":null,"content":null},{"coords":{"lat":null,"lng":null},"iconImage":null,"content":null}]  

here is my code I have no error messages just empty json.

require("../PHP/phpsqlajax_dbinfo.php");
$connection=odbc_connect($database, $username, $password);



if (!$connection)echo 'Failed to connect';

//Select Test statement 
$query="select 53.745 as lat,-0.338 as lng,'https://developers.google.com/maps/documentation/javascript/examples/full/images/beachflag.png' as iconImage, '<h1>Tony G</h1>' as content union all
select 53.745 as lat,-0.310 as lng,'https://maps.gstatic.com/mapfiles/ms2/micons/blue.png' as iconImage, '<h1>fred</h1>' as content ";


$result=odbc_exec($connection,$query);

//work through result and create JSON
while ($row = odbc_fetch_row($result)){
    $json[] = [
        'coords' => ['lat' => $row['lat'],'lng' => $row['lng']],
        'iconImage' => $row['iconImage'],
        'content' => $row['content'],
    ]; 
} 
echo json_encode($json);

I am a little puzzled as to what I am doing wrong.

thanks

Answer 1

Though it's unclear from manual where does data go to in odbc_fetch_row , it's clear that result ( true or false ) of this function is not what you expect. So, you should use another function, which returns array, in this case it is odbc_fetch_array :

while ($row = odbc_fetch_array($result)){
    $json[] = [
        'coords' => ['lat' => $row['lat'],'lng' => $row['lng']],
        'iconImage' => $row['iconImage'],
        'content' => $row['content'],
    ]; 
}