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==Example==
SupposeLet ''R''(''A'', ''B'', ''C'', ''D'') whichbe area relation schema known obey the set of functional dependencies ''F'' = {''A''→''B'', ''B''→''C'', ''CD→A''}. Suppose ''R'' is decomposed into relationsthree withrelation attributesschemas S<sub>1</sub> = {''A'', ''D''}, S<sub>2</sub> = {''A'', ''C''} and S<sub>3</sub> = {''B'', ''C'', ''D''}. andDetermining ''F''whether =this {''A''→''B'',decomposition ''B''→''C'',is ''CD→A''}lossless iscan given.be Thedone initialby tableauperforming fora thischase decompositionas show is:below.
The initial tableau for this decomposition is:
{| border="1" cellspacing="0" cellpadding="5" align="center"
! ''A'' !! ''B'' !! ''C'' !! ''D''
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