Comparison of Oracle 9i and 10G

Parameter / Metrics	Oracle 9i	Oracle 10G / 11G
SQL Optimizer	Both Cost Based and Rule Based Optimizers can be used	Cost Based Optimizer is used as a Default option. Rule Based cannot be used.
Data Export and Import	Can be done with the help of Export / Import feature	Comes with an additional feature of Oracle Data Pump.
Job Scheduling	Done by DBMS_JOB	Done with the help of DBMS_SCHEDULER
Table Space Point In Time Recovery(TSPITR)	Auxiliary Instance needs to be created Manually	Auxiliary Instance Automatically created while creation of Database or by using ReecoveryManager.
Database or Table space Roll back	Done with the Help of HOT / COLD backup of the database and recovery is required.	Roll back of the database or the table space can be done by enabling the Flashback database feature
Backup and Retention periods	The Old Backups are deleted manually or with the help of third party backup software.	The old Backups can be deleted automatically with the help of RMAN by setting the BAACKUP RETENTION POLICY PERIOD
Size of Backup Sets	Backup set compression cannot be done	Backup set can be reduced with the help of RMAN compression
Check point and UNDO tuning	These Parameters needs to be tuned based on the Performance of the Database manually. SQL tuning is done with the help of PGA_AGGREGATE_TARGET	Automatic tuning and SQL Tuning Advisories are available in 10G.
Database Performance Monitoring and tuning	Can be done with the help of STATSPACK and manually interpreting the same.	New feature called ADDM (Automatic Database Diagnostic Monitor) can be used for the collection of DBSTATS.
SGA and PGA Tuning	This is done manually based on the workload. Buffer Cache advisory needs to be turned ON to know the optimal value of the Buffer Cache.	Adjusted automatically based on workload.
Movement of Data files	Cannot be done.	Available and can be moved across platforms.
Segment Space Management	Use ASSM (Automatic Segment Space Management).Free space within the blocks is managed by bit-maps stored in the bitmap blocks in the given segment. Improves the performance in case of concurrent DML operations because respective operations can access different bitmap blocks reducing the contention on segment header.	ASSM available in 10g. Features are introduced which are built on ASSM e.g. qualifying segments for reclaiming free space, shrinking segments. These are useful features for avoiding the wastage of space resulted due to frequent DELETE operations.
Database Reorg	a) Move the tables within the table space or across table spaces b) using Exp/Imp.   Limitation of moving the object is that new object is created first and then the old object is dropped so in case of 10GB table, 10GB of free space must be present. Time is a major constraint for Exp/Imp operation.	No new object is created. The rows are physically moved to the blocks having adequate free space provided Automatic Segment Space Management is being used. This is less time consuming and needs no extra space.
Execute OS commands / Job Scheduling	Use JAVA stored procedures to execute OS command.	No need of developing JAVA stored procedures. New API i.e. DBMS_SCHEDULER has been introduced.
Rename table space.	Not Available.	Table space can be Renamed