隐含参数

http://blog.csdn.net/haiross/article/details/37905485

 

select * from v$version

 

>show parameter read_count;  

 

--查看和read_count相关的隐藏参数
sys@SYBO2SZ> @hidden_para
Enter value for para: read_count

KSPPINM                               KSPPSTVL             DESCRIB
-----------------------------------   -------------------- ---------------------------------------------
_db_file_exec_read_count              48                   multiblock read count for regular clients
_db_file_optimizer_read_count         8                    multiblock read count for regular clients
_db_file_noncontig_mblock_read_count  11                   number of noncontiguous db blocks to be prefetched
_sort_multiblock_read_count           2                    multi-block read count for sort