Watch out!
If you use PDO SQLSRV on windows 7, using 32 bit php on XAMMP, you might encounter driver problems : "This extension requires the Microsoft ODBC Driver 11 for SQL Server to communicate with SQL Server"
The reason, Microsoft 32-bit ODBC driver doesn't install properly on 64-bit Windows 7.
Check the solution to PDO SQLSRV driver problem here in StackOverflow
https://stackoverflow.com/a/46245990/1330248