有时候要改改表字段的某些精度，可能一多就不确定是否改全了，Oracle支持搜索table,字段,对象等统计信息

摘要: http://www.cnblogs.com/litou/p/3926881.html
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;