Fares Databases

Is it still necessary for many fares to be worked out by several
summations eg. on the basis of fare from minor town a) to major town b)
plus major town b) to major town c) plus major town c to minor town d)?
In other words do databases now exist which can immediately produce a
single fare from say Chatelherault to King's Nympton without the need
for the user to work it out in separate stages?
--
gordon

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