Comparing Dates in Openoffice Database with HSQLDB

I have a table in an Openoffice Database, containing two date columns. I'm trying to create a view that will aggregate all the rows in these columns and sum up the difference between these two columns in minutes开发者_高级运维.

This is pretty trivial, and in Postgres it would look like:

SELECT SUM(EndDate-BeginDate) AS total_minutes FROM mytable

What is the equivalent syntax in HSQLDB? I can't find much documentation on their date functions, and all the "standard" methods I'm familiar with return a syntax error.

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It's a similar syntax in HSQLDB 2.0

SELECT SUM((EndDate-BeginDate) MINUTE) AS total_minutes FROM mytable

In HSQLDB 1.8.x used in OpenOffice, try the DATEDIFF() function as documented in the HSQLDB Guide