To see the estimated space savings percentage for manually compressed BLC tables, issue a SELECT request on the BLCCompRatio column of the DBC.StatsV, DBC.TableStatsV, or DBC.TempTableStatsV views. For example:
SELECT blccompratio from dbc.statsv WHERE tablename = 'cvis001';
*** Query completed. One row found. One column returned.
*** Total elapsed time was 1 second.
BLCCompRatio
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86