MSSQL: SQLSTATE[] (null) (severity 0) after loading 1000 + lines - php

Question

I'm having some problems when returning a large number of rows from SQL Server using PHP + Datatables. My code is using one main loop then some "subloops".
Sometimes, when the number of lines gets up to 1000+ the execution is aborted and the error MSSQL: SQLSTATE[] (null) (severity 0) is shown.
Connection function:
function pdo_mssql($sql){
$host = ***;
$user = ***;
$pass = ***;
$db = ***;
try {
$PDO = new PDO( 'dblib:host=' . $host . ';dbname=' . $db, $user, $pass );;
}
catch ( PDOException $e ) {
echo 'MSSQL error: ' . $e->getMessage(); exit;
}
$result = $PDO->query( $sql );
if (is_array($result)){
$row = $result->fetchAll( PDO::FETCH_ASSOC );
}else{
$row = $result;
}
return $row;
}
Example of the script where the error occurs:
$sql = "SELECT ....";
$return = pdo_mssql($sql);
foreach ($return as $row){
$sql2 = "SELECT ...."
$return2 = pdomssql($sql2);
foreach ($return2 as $row2){
// Do something
}
$sql2 = "SELECT ...."
$return2 = pdomssql($sql2);
foreach ($return2 as $row2){
// Do something
}
$sql2 = "SELECT ...."
$return2 = pdomssql($sql2);
foreach ($return2 as $row2){
// Do something
}
// Show results
}
Does anyone have any suggestion to fix it?
Thanks

Answer 1

Please check the code, $return2 is not being assigned in inner loop. May be you want to do
$sql2 = "SELECT ...."
$return2 = pdomssql($sql2);