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119. View the Exhibit and examine the output of the query.
What do you infer from this?
A.The SGA_TARGET is a static parameter.
B.The instance is started, but the database is not yet open.
C.The server parameter file (SPFILE) was used to start the instance.
D.The SGA_TARGET parameter does not have any effect on the database instance until the
SGA_MAX_SIZE parameter is specified.
Answer: C
[email protected]> select name,value,isspecified from v$spparameter where name like '%sga%';
NAME VALUE ISSPEC
-------------------- -------------------- ------
sga_max_size FALSE
pre_page_sga FALSE
lock_sga FALSE
sga_target 0 TRUE
[email protected]> show parameter spfile
NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
spfile string /u01/app/oracle/product/11.2.0
/dbhome_1/dbs/spfiletest0924.o
ra
使用spfile启动时，sga_target 的isspecified为true，如果为false，则是使用pfile启动；
也可以通过 show parameter spfile这个方法，如果value有值，则说明使用spfile启动。如果没有值，则又pfile启动。
下面用pfile启动，然后再来查询这些
[email protected]> shutdown immediate
Database closed.
Database dismounted.
ORACLE instance shut down.
[email protected]> startup pfile='/u01/app/oracle/product/11.2.0/dbhome_1/dbs/inittest0924.ora';
ORACLE instance started.
Total System Global Area 3340451840 bytes
Fixed Size 2232960 bytes
Variable Size 3204451712 bytes
Database Buffers 117440512 bytes
Redo Buffers 16326656 bytes
Database mounted.
Database opened.
[email protected]> select name,value,isspecified from v$spparameter where name like '%sga%';
NAME VALUE ISSPEC
-------------------- -------------------- ------
sga_max_size FALSE
pre_page_sga FALSE
lock_sga FALSE
sga_target FALSE
[email protected]> show parameter spfile
NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
spfile string