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数据库启动之NOMOUNT

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Jun 07, 2016 pm 03:47 PM

startupstart updatabase

1.启动数据库：STARTUP命令后，执行顺序如下首先使用服务器上的SPFILESID文件启动实例，如未找到，使用服务器上默认的SPFILE启动实例；如未找到默认SPFILE,使用INITSID文件启动实例，如仍未找到，报错。 SYS@bys1startup; ORA-01078: failure in processing

1.启动数据库：STARTUP命令后，执行顺序如下

首先使用服务器上的SPFILESID文件启动实例，如未找到，使用服务器上默认的SPFILE启动实例；如未找到默认SPFILE,使用INITSID文件启动实例，如仍未找到，报错。

SYS@bys1>startup;
ORA-01078: failure in processing system parameters
LRM-00109: could not open parameter file '/u01/app/oracle/product/11.2.0/dbhome_1/dbs/initaaa.ora'

找到参数文件后，此时ORACLE根据参数文件中的设置创建实例，分配内存，启动后台进程。

可以在STARTUP 命令中使用PFILE选项指定参数文件来改变优先顺序：startuppfile=c:\orcl\pfile\init.ora

2.startup nomount

只启动实例不打开数据库中任何文件，不打开控制文件，只使用了初始化参数文件。这个过程也是启动数据库实例的过程。即读取参数文件，应用参数启动实例。

在WINDOWS上是ORCLE.EXE初始化，在UNIX/LINUX上是ORACLE可执行文件初始化。在操作系统中查看ORACLE可执行文件：WIN平台dir oracle.exe 或者 UNIX/LINUX平台 file oracle

此状态只有在创建数据库或重建控制文件时使用。此时ORACLE将进行如下工作：

分配SGA配置所有内存缓冲区和相关结构,启动所需全部后台进程，打开报警文件alertSID.log和追踪文件trace;

下面是实现启动的信息

SQL> conn sys/oraclesys as sysdba

已连接到空闲例程。

SQL> startup nomount;

ORACLE 例程已经启动。

Total System Global Area 431038464 bytes

Fixed Size 1375088 bytes

Variable Size 331351184 bytes

Database Buffers 92274688 bytes

Redo Buffers 6037504 bytes

3.实例启动时ALERT日志文件中的信息

在ALERT日志中可以看到实例启动时后台进程也相应启动，并且给出了PID及OSID信息。PID是进程在数据库内部的标识符编号，OSID代表进程在操作系统上进程编号。

通过数据库v$process视图，查询PID与SPID对应: v$process视图是操作系统到数据库的入口。

其中PID=1的进程是初始化数据库的进程，启动其它进程前即被占用，并在数据库中一直存在。SPID列代表操作上的进程号，通过查询SPID可以在OS中相应查询到进程。比如在操作系统中发现某进程占用高CPU/内存，可以通过进程号的对应找出相应的数据库进程，进行诊断优化。

Latchwait列代表进程当前正在等待的latch信息，Latchspin列记录进程正在通过SPIN进行Latch竞争。ADDR列代表进程地址、进程状态等信息在内存中记录。

Select addr,pid,spid,username,program,latchwait from v$process;

SunFeb 03 21:50:38 2013

StartingORACLE instance (normal)

LICENSE_MAX_SESSION= 0

LICENSE_SESSIONS_WARNING= 0

Pickedlatch-free SCN scheme 2

Autotuneof undo retention is turned on.

IMODE=BR

ILAT=27

LICENSE_MAX_USERS= 0

SYSauditing is disabled

Startingup:

OracleDatabase 11g Enterprise Edition Release11.2.0.1.0 - Production --------------数据库版本

Withthe Partitioning, OLAP, Data Mining and Real Application Testing options.

Usingparameter settings in server-side spfile C:\APP\ADMINISTRATOR\PRODUCT\11.2.0\DBHOME_1\DATABASE\SPFILEORCL.ORA

Systemparameters with non-default values:

processes = 150

large_pool_size = 8M

memory_target = 412M

control_files ="D:\DISK1\CONTROL01.CTL" --------------------参数文件中的参数

control_files ="D:\DISK2\CONTROL02.CTL"

control_files ="D:\DISK3\CONTROL03.CTL"

control_files ="D:\DISK4\CONTROL04.CTL"

control_files ="D:\DISK5\CONTROL05.CTL"

db_block_size = 8192

db_cache_size = 32M

db_cache_advice = "ON"

compatible = "11.2.0.0.0"

log_archive_dest_1 = "location=d:\disk1\offlinelog\mandatory"

log_archive_dest_2 = "location=d:\disk2\offlinelog\"

log_archive_dest_3 = "location=d:\disk3\offlinelog\optional"

log_archive_dest_4 = "location=d:\disk4\offlinelog\optional"

log_archive_dest_5 = "location=d:\disk5\offlinelog\mandatory"

log_archive_dest_state_1 = "ENABLE"

log_archive_min_succeed_dest= 3

db_recovery_file_dest ="C:\app\Administrator\flash_recovery_area"

db_recovery_file_dest_size= 3852M

undo_tablespace = "UNDOTBS1"

remote_login_passwordfile="EXCLUSIVE"

db_domain = ""

dispatchers = "(PROTOCOL=TCP)(SERVICE=orclXDB)"

audit_file_dest ="C:\APP\ADMINISTRATOR\ADMIN\ORCL\ADUMP"

audit_trail = "DB"

db_name = "orcl"

open_cursors = 300

diagnostic_dest = "C:\APP\ADMINISTRATOR"

SunFeb 03 21:50:38 2013

PMONstarted with pid=2, OS id=2396

SunFeb 03 21:50:38 2013

VKTMstarted with pid=3, OS id=2408 at elevated priority

VKTMrunning at (10)millisec precision with DBRM quantum (100)ms -----------------------后台进程启动

SunFeb 03 21:50:38 2013

GEN0started with pid=4, OS id=612

SunFeb 03 21:50:38 2013

DIAGstarted with pid=5, OS id=2100

SunFeb 03 21:50:38 2013

DBRMstarted with pid=6, OS id=2332

SunFeb 03 21:50:38 2013

PSP0started with pid=7, OS id=2072

SunFeb 03 21:50:38 2013

DIA0started with pid=8, OS id=2404

SunFeb 03 21:50:38 2013

MMANstarted with pid=9, OS id=2400

SunFeb 03 21:50:38 2013

DBW0started with pid=10, OS id=2356

SunFeb 03 21:50:38 2013

LGWRstarted with pid=11, OS id=2484

SunFeb 03 21:50:38 2013

CKPTstarted with pid=12, OS id=2488

SunFeb 03 21:50:38 2013

SMONstarted with pid=13, OS id=2352

SunFeb 03 21:50:38 2013

RECOstarted with pid=14, OS id=2376

SunFeb 03 21:50:38 2013

MMONstarted with pid=15, OS id=2360

SunFeb 03 21:50:38 2013

MMNLstarted with pid=16, OS id=2512

startingup 1 dispatcher(s) for network address'(ADDRESS=(PARTIAL=YES)(PROTOCOL=TCP))'...

startingup 1 shared server(s) ...

ORACLE_BASEfrom environment = C:\app\Administrator

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