function for date difference ?

On Friday 30 June 2000, at 14 h 54, the keyboard of jprem <jprem@srmsoft.co.in>
wrote:

is there any built-in function to find the difference between any two
dates in postgresql 6.5.3 ?

You can do substraction on dates.

SELECT ending - starting FROM intervals;
SELECT * FROM intervals WHERE ending - starting > 86400::timespan;

If you want something more sophisticated, you have to read the dates into a
program (I do it with Perl) and use this program to perform all the operations
you wish.