Oracle Audio Technologies B10508-01 ユーザーズマニュアル

Other Recommendations

Oracle9i Installation Guide Release 2 (9.2.0.2) for HP Alpha OpenVMS

Check statistics, such as V$SYSSTAT, to see if the number of sorts to disk is high 
compared to in-memory sorts

.  

If it is, then increase the value of SORT_AREA_

SIZE.

Check the size in number of rows of the tables involved in the query, and translate 
this size into total number of blocks

.  

Based on the query, try to fit as many of the 

hard hit table blocks in DB_BLOCK_BUFFERS.

For example, if there are four tables involved in the query, but columns from one of 
the tables are used repeatedly in the "where" clause in joins, "in", etc.; try to fit as 
many blocks from this table as possible into the cache to see if 
DB_BLOCK_BUFFERS can be increased

.  

To ensure the hard hit tables are cached 

and stay in the most recently used (MRU) end of the cache, perform either of the 
following steps:

■

Type (using SQLPLUS),

alter table <tablename> cache

or

■

At the time of creation,

 create table <tablename> ... cache

If there are enough buffers to accommodate all blocks from all tables involved in the 
query, use the alter command to cache all the blocks

.  

The purpose is to cache most 

blocks into memory to ensure that I/O to disks is eliminated or remains low.