PHP Associative array keys get shortened

Question

I am having an issue where the keys of an associative array created from a SQL query (Oracle ODBC) are being shortened. I've never come across this before. Using the SQL below the array ends up as

0:
  UPSTREAMCI_LOGI => xxxxxxxxxxxxxxxxxxxxxxxxxxx
  DOWNSTREAM_LO => xxxxxxxx

$sql = "SELECT UPSTREAMCI_LOGICAL_NAME, DOWNSTREAMCI_LOGICAL_NAME WHERE SYSMODTIME >= TO_DATE('2017-04-29', 'yyyy-mm-dd')";
$result = odbc_exec($connect, $sql);
$dbinfo = array();
while ($row = odbc_fetch_array($result)) {
    $dbinfo[] = $row;
}