PHP Excel导出删除前导零

我有一个脚本来导出MySQL数据库的内容，该数据库除了在具有前导零的列上工作良好之外。由于某些原因，它们被丢弃了。

是否有一种方法可以修改代码以保留那些前导零?

多谢!

$sql = "Select * from $DB_TBLName";
$Connect = @mysql_connect($DB_Server, $DB_Username, $DB_Password) or die("Couldn't connect to MySQL:<br>" . mysql_error() . "<br>" . mysql_errno());
//select database   
$Db = @mysql_select_db($DB_DBName, $Connect) or die("Couldn't select database:<br>" . mysql_error(). "<br>" . mysql_errno());   
//execute query 
$result = @mysql_query($sql,$Connect) or die("Couldn't execute query:<br>" . mysql_error(). "<br>" . mysql_errno());    
$file_ending = "xls";
//header info for browser
header("Content-Type: application/xls");    
header("Content-Disposition: attachment; filename=$filename.xls");  
header("Pragma: no-cache"); 
header("Expires: 0");
/*******Start of Formatting for Excel*******/   
//define separator (defines columns in excel & tabs in word)
$sep = "'t"; //tabbed character
//start of printing column names as names of MySQL fields
for ($i = 0; $i < mysql_num_fields($result); $i++) {
echo mysql_field_name($result,$i) . "'t";
}
print("'n");    
//end of printing column names  
//start while loop to get data
    while($row = mysql_fetch_row($result))
    {
        $schema_insert = "";
        for($j=0; $j<mysql_num_fields($result);$j++)
        {
            if(!isset($row[$j]))
                $schema_insert .= "NULL".$sep;
            elseif ($row[$j] != "")
                $schema_insert .= "$row[$j]".$sep;
            else
                $schema_insert .= "".$sep;
        }
        $schema_insert = str_replace($sep."$", "", $schema_insert);
        $schema_insert = preg_replace("/'r'n|'n'r|'n|'r/", " ", $schema_insert);
        $schema_insert .= "'t";
        print(trim($schema_insert));
        print "'n";
    }