Identifying Teradata table skew query

SAMPLE TABLE SKEW IDENTIFYING QUERY:

 Lock Dbc.TableSize For Access 

Lock Dbc.tables For Access 

SELECT B.databasename , B.TableName , A.LastAccessTimeStamp , SUM ( currentperm ) ( NAMED CurrentPerm ) ,

 MAXIMUM ( currentperm ) ( NAMED MaxPerm ) , AVG ( currentperm ) ( NAMED AvgPerm ) ,

 ( ( MAXIMUM ( currentperm ) - AVG ( currentperm ) ) * 100.0 ) / ( MAXIMUM ( currentperm ) ) ( NAMED SkewPercent ) 

FROM dbc.tablesize B INNER JOIN DBC.TABLES A 

 ON A.DATABASENAME = B.DATABASENAME 

 AND A.TABLENAME = B.TABLENAME 

WHERE B.DATABASENAME = <my_database>

GROUP BY 1 , 2 , 3 

HAVING ( ( MAXIMUM ( currentperm ) - AVG ( currentperm ) ) * 100.0 ) / ( MAXIMUM ( currentperm ) ) > 20 

ORDER BY 1 , 2 ;