SYSCAT.COLGROUPDISTCOUNTS catalog view
Each row represents the distribution statistics that apply to the nth most frequent value of a column group or the nth quantile of a column group.
Column Name  Data Type  Nullable  Description 

COLGROUPID  INTEGER  Identifier for the column group.  
TYPE  CHAR (1) 


SEQNO  SMALLINT  Sequence number n representing the nth TYPE value.  
VALCOUNT  BIGINT  If TYPE = F, VALCOUNT is the number of occurrences of COLVALUE for the column group with this SEQNO. If TYPE = Q, VALCOUNT is the number of rows whose value is less than or equal to COLVALUE for the column group with this SEQNO. 

DISTCOUNT  BIGINT  If TYPE = Q, this column records the number of distinct values that are less than or equal to COLVALUE for the column group with this SEQNO (the null value if unavailable). 