php - MySQLi returns erroneous results -

i've encountered problem while using mysqli , can't figure out why happening.

on mariadb 5.5.41 server have table tbl1

a | b --+-- 1 | 1 

i've created following php script:

<?php $db_host="localhost"; $db_user="user"; $db_pass="pass"; $db_db="db_test";  // mysqli test $db_link = @new mysqli($db_host,$db_user,$db_pass,$db_db);  if($db_link->connect_error) die("mysqli connect error");  $result = $db_link->query("select tbl1 b='1'"); if(!$result) {   die("mysqli query error"); } else {   die("row count:".$result->num_rows); } ?> 

and result is:

row count:0 

but if use following code:

<?php $db_host="localhost"; $db_user="user"; $db_pass="pass"; $db_db="db_test";  //mysql $db_link = @mysql_connect($db_host,$db_user,$db_pass); if(!$db_link) die("mysql connect error"); mysql_select_db($db_db,$db_link);  $result = mysql_query("select tbl1 b='1'"); if(!$result) {   die("mysql query error"); } else {   die("row count:".mysql_num_rows($result)); } ?> 

and result is:

row count:1 

any ideas why happens ?

mysqli_fetch_row in php manual mysqli_fetch_row