我们知道Oracle在启动过程中需要读取参数文件（pfile/spfile）来创建实例Oracle在启动过程中寻找参数文件的顺序为
spfile<sid>oraspfileorainit<sid>ora
而创建实例的过程中Oracle需要的最少参数为一个即db_name参数
我们来看一个测试启动一个任意设置的实例本例ORACLE_SID=julia
oracle@jumper dbs]$ export ORACLE_SID=julia[oracle@jumper dbs]$ sqlplus / as sysdbaSQL*Plus: Release Production on Mon May :: Copyright (c) Oracle Corporation All rights reservedConnected to an idle instanceSQL> startup nomount;ORA: failure in processing system parametersLRM: could not open parameter file /opt/oracle/product//dbs/initjuliaora
Oracle最后检查的文件为initjuliaora让我们创建这个文件然后数据库实例即可创建
SQL> ! echo db_name=julia > /opt/oracle/product//dbs/initjuliaoraSQL> startup nomount;ORACLE instance startedTotal System Global Area bytesFixed Size bytesVariable Size bytesDatabase Buffers bytesRedo Buffers bytes
我们可以看一下缺省的各类文件的存储地点
SQL> show parameter dump_dest NAME TYPE VALUE background_dump_dest string ?/rdbms/log core_dump_dest string ?/dbs user_dump_dest string ?/rdbms/log SQL> show parameter control_files NAME TYPE VALUE control_files string ?/dbs/cntrl@dbf
我们顺便看一下缺省的警报日志中记录的信息
oracle@jumper dbs]$ cat $ORACLE_HOME/rdbms/log/alert_julialogMon May :: Starting ORACLE instance (normal)Mon May :: WARNING: EINVAL creating segment of size xfix shm parameters in /etc/system or equivalentLICENSE_MAX_SESSION = LICENSE_SESSIONS_WARNING = SCN scheme Using log_archive_dest parameter default valueLICENSE_MAX_USERS = SYS auditing is disabledStarting up ORACLE RDBMS Version: System parameters with nondefault values: db_name = juliaPMON started with pid=DBW started with pid=LGWR started with pid=CKPT started with pid=SMON started with pid=RECO started with pid=
