Currently , Oracle has released Oracle 10g (ten grid). but most used version is 9.
1. Oracle Install
You can install oracle 10g in linux or windows(2000,xp,2003)
The process of oracle 10g is mostly as same as oracle 9. but the sys, system,sysman and other default users should change their password when in stall for security.
After you finished installment, you would find it's more simple than oracle 9. and the oem (oracle enterprise manager) and other tools are based on web explorer without desktop graphic applications support.
some urls as follow:
. ultra search url, http://peter:5620/ultrasearch
. iSQL *Plus URL, http://peter:5620/isqlplus
. Enterprise Manager, http://peter:5620/em
2. Some Basic Concepts
. What's is Instance? What's Database?
Instance is a series of proceses which service for oracle database. Database is a collection of files, such as database files (*.dbf), log files (*.log),control files (*.ctl) .Oracle system first loads ctl files and then dbf files.
Notice: In sqlplus ,you can view these files .
HOWTO: sqlplus "sys/password as sysdba"
DESC v$controlfile ( v$datafile,v$logfile)
SPFILETEST.ORA is a very important parameter file.
->control files -> logfiles
3 . Physical Structure: SPFILE -[
(File structure) ->control files -> database files
4 . Memery Structure: Oracle instantce will alloc a SGA memery.
SGA: the most important structure.
DB buffer: improve performance. cache . the biggest buffer.
keep cache pool , regenerate cache pool, default cache pool
Share buffer: dictionary cache , lib cache (share sql and pl/sql)
share sql: keep compiled sql in buffer, share , reuse
pl/sql: keep compiled pl/sql.
dictionary: cache some table name, column type , restrict and etc.
Redo buffer: FIFO buffer.
Big Share district: an optinal buffer
Fixed SGA: you can not resize the buffer.
5. Logical Structure.
datafile <-n:1->tablespace<-1:n->segment(段)<-1:n->extent(盘区,拓展,范围)<-1:n-> block (window:8k. you can adjust the size when install globle db, but size must be integral multiple of 8k size)