4. The method of claim 3 , wherein the one or more jurisdiction-dependent constraints include at least one of a non-null constraint, a maximum-number constraint, a constraint on the kind of taxation level, an exclusive-OR constraint between different taxation levels or kinds of taxation levels, and an AND constraint between different taxation levels or kinds of taxation levels.
3. The method of claim 1 , wherein the data schema includes one or more jurisdiction-dependent constraints on the taxation-line-item entities associated with a taxation-line entity.