Date comparisons in SQLite on Android

I have been tripped up a few times using date comparisons in SQLite. This is where I pass in a correctly formatted date string and want rows from the database which are equal to this for example.

I get this to work in a couple of steps:

1. Every date I put in the database goes through this method. It tries to parse the date according to a pattern I have defined and if the date wont parse, returns a null.

public static String dateForDb(String date) {

String formattedDate = null;

try {

Date d = null;

d = DateFactory.SDF_SHORT.parse(date);

if (d != null) {

formattedDate = DateFactory.SDF_SHORT.format(d);

}

} catch (Exception e) {

e.printStackTrace();

}

return formattedDate;

}

This ensures that everything that gets into my database is correctly formatted for the next bit.

2. In my sql statement I take out the date = string stuff and replace it with a static call to this method:

public static String dbDateCompare(String columnName, String dateValue) {
return "strftime('%Y-%m-%d', " + columnName + ") = '"
+ dateValue + "'";
}

This uses the strftime sqlite function to get the date from the db in a format that is string comparable to the date string passed in. 

Just for reference here is my SimpleDateFormat, but you can format your dates any way you like:

public static final SimpleDateFormat SDF_SHORT = new SimpleDateFormat(

"yyyy-MM-dd");

References:
SQLite date and time function: http://www.sqlite.org/lang_datefunc.html
The JDK 7 version of SimpleDateFormat: http://download.oracle.com/javase/7/docs/api/java/text/SimpleDateFormat.html