A new technique based on H\"older's integral inequality is applied to QCD
sum-rules to provide fundamental constraints on the sum-rule parameters. These
constraints must be satisfied if the sum-rules are to consistently describe
integrated physical cross-sections, but these constraints do not require any
experimental data and therefore can be applied to any hadronic spectral
function. As an illustration of this technique the Laplace sum-rules of the
light-quark correlation function for the vector and the axial-vector currents
are examined in detail. We find examples of inconsistency between the
inequalities and sum-rule parameters used in some previous analyses of the
vector and axial-vector channels.Comment: 13 pages, RevTeX, 4 figures available upon request, to appear in
Phys. Lett