The SQLite library is not included by default, it is necessary to modify the PHP.INI file in the directory of PHP and activate two lines, by removing the semicolon in prefix:
You can run SQLite in Using PHP and SQL locally with Wamp.

To verify that SQLite works

The script for SQLite 3 (since PHP 5.4)
  die("SQLite 3 NOT supported.");
$base=new SQLite3($dbname, 0666);
echo "SQLite 3 supported."; 

The script for SQLite 2:
$base=new SQLiteDatabase($dbname, 0666, $err);
if ($err)
  die("SQLite NOT supported.");
echo "SQLite supported.";
This code creates the database named 'scanftree'. If the extension is not available, the variable $base will be false. If it works, a file named base appears in the directory of the script.