Queries spinning CPU

Hi Team,

We could see the below queries spinning CPU in statspack report. kindly let me know the reason for this.

    CPU                  CPU per             Elapsd                     Old

  Time (s)   Executions  Exec (s)  %Total   Time (s)    Buffer Gets  Hash Value

---------- ------------ ---------- ------ ---------- --------------- ----------

    743.79      931,609       0.00   30.3     796.63      45,087,847  559922008

Module: JDBC Thin Client

SELECT NULL  AS table_cat, t.owner  AS table_schem, t.table_name

AS table_name, t.column_name AS column_name, decode (t.data_typ

e, 'CHAR', 1, 'VARCHAR2', 12, 'NUMBER', 3, 'LONG', -1, 'DATE', 9

3, 'RAW', 3, 'LONG RAW', 4,  'BLOB', 2004, 'CLOB', 2005, 'BFILE'