select a.owner, a.table_name, b.column_name,b.data_precision || ',' ||b.data_scale
      from dba_tables a, dba_tab_columns b, dba_objects c
     where a.owner = b.owner
       and a.table_name = b.table_name
       and a.table_name = c.object_name
       --and a.owner in ('XXX') --用户可选
       --and b.data_type in ('VARCHAR2','CHAR','NCHAR','NCLOB','NVARCHAR2','NUMBER','DATE','TIMESTAMP%','FLOAT')
       and c.object_type = 'TABLE'
       and  upper(b.column_name) like '%BG_NUM%'
       order by a.owner,a.table_name,b.column_id;