Database Abstraction with Sqlite

I am trying it to make an application in Windows platform using Sqlite at back-end. Throughout the code i have used database abstraction using PEAR. The problem i am facing is that whenever a querry suppose to return nothing , it is throwing error: unknown error, otherwise its woring fine.

ex:

table: A B
1 php
2 jav
3 VB

$sql="select * from table where a=10";
$db-->query($sql);

It gives error;

Please help how to avoid this.