“…In order to reach a compromise between simplicity and flexibility, the authors chose a star-like databaseschematorepresentthemathematicalmodel,asshowninFigure3.Noticethegivenschema isneitherastarschemanoranERschema:itisahybridrepresentation.Duringtheinitialstageof theproject,itwasastar-schema,becauseitprovidesabasicschemathatcouldbegrownwithnew cubedimensions,dependingonadditionalinformationgivenbyusers'requirements.Butontheother hand,unfortunately,therecursiveparsertreestructurecouldnotberepresentedasapurestarschema, because it required a recursive node entity (Karwin, 2010;Celko, 2004). Therefore, introducing many-to-many(M:N)relationshipsintothestarschemathatoriginallyhadonlyone-to-many(1:N) relationshipswasnecessary.However,theauthorsmadeanefforttomaketheschemaassimilaras possibletoanactualstar-schemainordertoeasilyaddnewdimensionstothemodel,whichwould allowstoringusefulinformationabouttheequations(e.g.,dateofinsertion,experiment,nameof theexperimenter,etc).Forinstance,eachequationcanbelinkedtotheexperimenterwhoaddedthe equations.Theexperimenterhaspersonalinformationattributes(id,name,position,etc),butsuch personisalsopartofateam,whichispartofadepartment.Therefore,theexperimenterdimension hasthefollowinghierarchy:department<team<experimenter.Thenthestar-likeschemagives theopportunitytoperformaggregationoperationssuchasRoll-UporDrill-Down,inordertogroup equationsthatbelongstothesameexperimenter,thesameteam,orthesamedepartment.Similarly, addingthedateofinsertionoftheequationsinducesanadditionaltimedimension.Thenequations canbeaggregatedbymonth,yearoratimerange,whichcanhelptrackingthelaboratoryactivity.…”