DTD for the business requirement XML structure
<!ELEMENT cube (dimensions,measures,slicers?,aggregations?)> <!ELEMENT dimensions (concept+)> <!ELEMENT concept (function?,role?,nfr*)*> <!ELEMENT function (#PCDATA)> <!ELEMENT role (#PCDATA)> <!ELEMENT nfr (#PCDATA)> <!ELEMENT measures (concept*)> <!ELEMENT slicers (comparison+)> <!ELEMENT comparison (concept,function?,operator,value)> <!ELEMENT operator (#PCDATA)> <!ELEMENT value (#PCDATA)> <!ELEMENT aggregations (aggregation*)> <!ELEMENT aggregation (dimension,measure,function?)> <!ELEMENT dimension EMPTY> <!ELEMENT measure EMPTY> <!ATTLIST concept id CDATA #REQUIRED> <!ATTLIST concept alias CDATA #IMPLIED> <!ATTLIST nfr kind (freshness|precision) #REQUIRED> <!ATTLIST nfr format CDATA #IMPLIED> <!ATTLIST nfr value CDATA #IMPLIED> <!ATTLIST aggregation order CDATA #IMPLIED> <!ATTLIST dimension refID CDATA #REQUIRED> <!ATTLIST dimension refAlias CDATA #IMPLIED> <!ATTLIST measure refID CDATA #REQUIRED> <!ATTLIST measure refAlias CDATA #IMPLIED>