Storing SQL Server 2005 datetime

I have a php script inserting values in to SQL Server 2005 table via SQL

$date = '15 Jun 2011 00:00';
$sql = "INSERT INTO shows ( DateStart ) VALUES ( '$date')"; 

I have 2 issues:

1) how best to convert this date into something SQL Server understands? The default format is mm/dd/yyyy on my system but I want to present the dates 开发者_如何学Cas readable to the user.

2) When inserting an empty string the DateStart value gets set to 1/1/1900. How best to convert an "invalid" date into a NULL (the column already accepts NULLs) so that if $date = "" then DateStart IS NULL

Thanks!

• Point 1: Use ISO date format YYYY-MM-DDTHH:MM:SS
  Note: For date only use YYYYMMDD becuase of anomalies in how SQL Server parse dates
• Point 2: NULLIF(value, '')

1. I think the datetime format while inserting the record in datetime column should always "YYYY-MM-DD HH:MM:SS" Default Format

2. gbn already told.