[xquery-talk] Re: The State of Native XML databases

[John Snelson]

Andrew Welch wrote:
> But it can only do any of those things if you tell it that the String
> '2007-08-21' is a date, and not just a String?
> 
> Giving <date>2007-08-21</date> to the database can't be enough...

Sure, that's why XSLT and XQuery allow you to cast values - there are 
even special rules that automatically cast values from an untyped XML 
document which make life easier in that case.

> The way I was reading this thread was that if the type information was
> stored in the database, the cost of creating the xs:date would be
> incurred once and not once per query that uses the value?

That's possible, but not mandatory. Besides, parsing a date string is 
probably not going to be the bottleneck in a well designed XML database.

John