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¡¡¡¡ÔõÑù²ÅÄÜͨ¹ýORACLE8DBA(OCP)¿¼ÊÔ
¡¡¡¡Hi, little fish
¡¡¡¡I can share my tips, but I find your website have not the oracle
¡¡¡¡You can add it. If my tips can help you, tell me.
¡¡¡¡Best regards,
¡¡¡¡Sandy

¡¡¡¡--------------------------------------
¡¡¡¡How to pass the ORACLE 8 DBA(OCP) exam:

¡¡¡¡1. Get and read the student books from oracle or your friend(12 total), all
¡¡¡¡2. Do the assess exam.(run the attachment file assess.exe to install it).
£¨Download assess.exe£©.
¡¡¡¡3. You can find more information at Oracle website.
¡¡¡¡4. Other tips below:
¡¡¡¡1Z0-001 - Into to Oracle: SQL and PL/SQL
¡¡¡¡1.An expr. with NULL always evaluates to NULL, except ||, which treats NULL
¡¡¡¡2.Comparison to NULL is always FALSE
¡¡¡¡3.All functions, except COUNT(*), ignores NULL values
¡¡¡¡4.NULLS are displayed last with ORDERED BY in Oracle8
¡¡¡¡5.Logical evaluation: TRUE takes precedence with OR, FALSE with AND
¡¡¡¡6.There are a lot of questions about GROUP BY/ HAVING...
¡¡¡¡7.Use WHERE to exclude rows, HAVING to exclude groups from a query
¡¡¡¡8.Know when a cartesian product will be formed. You need a min of N-1
¡¡¡¡9.Know the difference between an equi (=), self (must use tab aliases), outer
¡¡¡¡10.You can only have a subquery in a FROM/ WHERE/ HAVING clause of a SELECT
¡¡¡¡11.Sub-queries and VIEWS cannot contain ORDER BY
¡¡¡¡12.A literal is any char/num/expr in a SELECT LIST that¡¯s not a col or col
¡¡¡¡13.MIN and MAX are the only functions that can operate on any datatype
¡¡¡¡14.PRIMARY KEY and UNIQUE constraints will implicitly create INDEXES
¡¡¡¡15.There is a lot of questions like: "Which line will return an error?". Look
for names starting with numbers, invalid constraints, etc.
¡¡¡¡1Z0-013 - Oracle8: Database Administration

¡¡¡¡1.INSTANCE=SGA + background processed (not server processes); INSTANCE will
¡¡¡¡2.SGA=System Global Area/ PGA=Program Global Area
¡¡¡¡3.Oracle server creates PGA as writeable and non-shared/ SGA as shared
¡¡¡¡4.Know what background processes are doing in detail, DBWR, SMON, PMON, LGWR,
¡¡¡¡5.SMON coalesces adjacent free extents into larger extent
¡¡¡¡6.Server processes executes SQL; Main phases are PARSE (setup parse tree=most
effective search path), EXECUTE (apply parse tree) and FETCH (get rows)
¡¡¡¡7.Server configurations: single-task, two-task (dedicated server), MTS
¡¡¡¡8.Shared Server: SQL*Net2/8 required, one requestQ for system, responseQ per
¡¡¡¡9.Dedicated Server: use for batch, connect internal, server manager
¡¡¡¡10.With shared server session data and cursor state moves to SGA, stack space
¡¡¡¡11.No quota means segments cannot grow or be created, only object owner needs
¡¡¡¡12.By default a user has no access to any TS

¡¡¡¡13.If quota=0 NO ACCESS; -1=UNLIMITED (see view sys.dba_ts_quotas)
¡¡¡¡14.Clusters pre-allocate space/ 2 types: index clusters (stored together for
faster join performance) and hush clusters
¡¡¡¡15.I¡¯ve got about 3 questions on index clusters and none about hush clusters
¡¡¡¡16.Sysprivs and roles use WITH ADMIN OPTION, use WITH GRANT OPTION for object
¡¡¡¡17.Revoke a GRANT...WITH ADMIN OPTION is not hierarchical and will not
¡¡¡¡18.Know how to calculate the size of the N nd extend. INITIAL, NEXT, NEXT :=
¡¡¡¡19.PCTUSED is not valid for indexes; OPTIMAL is only valid for rollsegs;
PCTINCREASE for rollsegs is 0 (cannot be set)
¡¡¡¡20.There are at least 3 questions about what will happen when PCTFREE/PCTUSED
¡¡¡¡21.MAXTRANS applies to all blocks; INITRANS to new blocks only (23 bytes per
¡¡¡¡22.Run orapwd utility before setting REMOTE_LOGIN_PASSWO
RDFILE=EXCLUSIVE|SHARED; Grant OSDBA/OSOPER to users; Check V$PWFILE_USERS
¡¡¡¡23.DB_NAME is the only mandatory parm; DB_BLOCK_SIZE cannot change after db
¡¡¡¡24.Defaults: DB_BLOCK_SIZE=2K/ DB_BLOCK_BUFFERS=60/ SHAR
¡¡¡¡25.Must have at least one control file and 2 log groups
¡¡¡¡26.Read consistency: readers do not block writers and writers do not block
¡¡¡¡AUDIT_TRAIL=DB uses SYS.AUD$ table, view via DBA_AUDIT_TRAIL
¡¡¡¡27.Use AUDIT SELECT for sequences
¡¡¡¡28.You need to set RESOURCE_LIMIT=TRUE for PROFILES (resource checking)
¡¡¡¡29.One can DROP from a READ ONLY ts
¡¡¡¡1Z0-014 - Oracle8: Performance Tuning Workshop
¡¡¡¡1.Tuning process is ITERATIVE and PROGRESSIVE
¡¡¡¡2.Many inserts/updates with OLTP, many table scans with DSS
¡¡¡¡3.By default the SYSTEM tablespace will be used for sorts, CHANGE IT!!!
¡¡¡¡4.SEP=Sort Extent Pool is in SGA, Sorts are done in user memory except with
¡¡¡¡5.Use DBMS_APPLICATION_INFO to register and track modules/ created with
dbmsutil.sql/ See V$SQLAREA and V$SESSION
¡¡¡¡6.OPTIMIZER_MODE is for instance, OPTIMIZER_GOAL is for session
¡¡¡¡7.RULE is based on rank/ COST is based on lowest relative cost/ COOSE goes to
¡¡¡¡8.TKPROF: Logical reads = QUERY (logical reads in consistent mode) + CURRENT
¡¡¡¡9.V$SYSSTAT: Logical reads = consistent gets + db block gets
¡¡¡¡10.Tune table scans: DB_FILE_MULTIBLOCK_READ_COUNT=/ CACHE_SIZE_THRESHOLD=

¡¡¡¡13.V$CACHE is usefull for Oracle Parallel Server
¡¡¡¡14.Set DB_BLOCK_LRU_LATCHES if you have misses in V$LATCH

¡¡¡¡16.Latches can be WILLING-TO-WAIT (eg redo allocation) or NOWAIT (eg redo
¡¡¡¡17.Oracle maintains all locks as ENQUEUES/ Deadlocks are resolved at
¡¡¡¡18.Lock modes: RX=DML/ TM=table/ TX=transaction and rollseg/ RS=SELECT... FOR
UPDATE/ SRX=DML and no SELECT FOR UPDATE/ UL=user lock/ S=prevents any DML
¡¡¡¡19.Index foreign key column on child table to prevent SHARE lock during DML
¡¡¡¡20.Use SID and Serial# in V$SESSION to kill a session
¡¡¡¡21.Impact of reducing DB_BLOCK_BUFFERS: Set DB_BLOCK_LRU_STATISTICS= and
¡¡¡¡22.Impact if increasing DB_BLOCK_BUFFERS: Set DB_BLOCK_E
XTENDED_LRU_STATISTICS= and query V$KCBCBH
¡¡¡¡23.To keep sorts in memory, increase SORT_AREA_SIZE
¡¡¡¡24.SORT_WRITE_BUFFERS (16k - 32k) * SORT_WRITE_BUFFER_SIZE (2-8) +
¡¡¡¡25.Any MTS parameter may be wrong, but if MTS_SERVICE=SID, you will get a
dedicated server connection if shared cannot be established
¡¡¡¡1Z0-015 - Oracle8: Backup and recovery Workshop
¡¡¡¡1.Backups types: Image copies (operating system backups) or logical backups
¡¡¡¡2.Files to backup: select * from v$controlfile/v$datafile/v$logfile, init.ora
¡¡¡¡3.NOARCHIVELOG mode is default, you need to switch to ARCHIVELOG to do
¡¡¡¡4.You can only switch log mode in MOUNT-state (STARTUP MOUNT). You need ALTER
¡¡¡¡5.LOG_ARCHIVE_START=TRUE will start ARCH process
¡¡¡¡6.An on-line DB is backed up tablespace by tablespace. Use the ALTER
TABLESPACE BEGIN BACKUP command (Not READ ONLY tablespaces!!!)
¡¡¡¡7.Exp/imp DIRECT=YES uses RECORDLENGTH= and not BUFFER=. Data written
directly to TTC (Two task common buffer) and bypasses BUFFER CACHE
¡¡¡¡8.Use exp CONSISTENT=YES if you need to preserve integrity between tables.
¡¡¡¡9.INCTYPE=INCREMENTAL - objects changed since last export of any type/
INCTYPE=CUMULATIVE - obects changed since last cumulative export
¡¡¡¡10.You cannot roll forward after a logical recovery (ie apply redo log files
¡¡¡¡11.After DB structure changes (know when - 2-3 questions) do an ALTER
¡¡¡¡12.Complete Recovery: DATABASE/ TABLESPACE/ DATAFILE based
¡¡¡¡13.Incomplete Recovery: TIME (YYYY-MM-DD:HH24:MI:SS)/ CANCEL/ CHANGE based
¡¡¡¡14.Incomplete recovery not possable on SYSTEM ts or ts with active rollsegs.
¡¡¡¡15.Be careful not to confuse CANCEL and CHANGED based recovery.
¡¡¡¡16.All datafiles must be restored for an incomplete recovery. Incomplete
¡¡¡¡17.After incomplete recovery, do an OPEN RESETLOGS and take a backup.
¡¡¡¡18.If LOG_BLOCK_CHECKSUM=TRUE and checksum fails: ALTER DATABASE CLEAR
¡¡¡¡19.Use DBVERIFY (dbv file=...) to check offline datafiles for structural
damage (be careful, the training guide incorrectly states that both On-line and
¡¡¡¡1Z0-016 - Oracle8: Network Administration
¡¡¡¡1.The exam is easy, but take care of it, some answer is out of your image.
¡¡¡¡2.At chapter 1,2 and 3, the answer is ambigious. It is easy to lose your
scores.



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