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Oracle 9i : Some of limitation on Oracle 9i

February 23, 2011 8:21 am / 1 Comment on Oracle 9i : Some of limitation on Oracle 9i


Physical Database Limits

Item Type of Limit Limit Value
Database Block Size Minimum 2048 bytes; must be a multiple of operating system physical block size
Maximum Operating system dependent; never more than 32 KB
Database Blocks Minimum in initial extent of a segment. 2 blocks
Maximum per datafile Platform dependent; typically 222-1 blocks
Controlfiles Number of control files 1 minimum; 2 or more (on separate devices) strongly recommended
Size of a control file Dependent on operating system and database creation options; maximum of 20,000 x (database block size)
Database files Maximum per tablespace Operating system dependent; usually 1022
Maximum per database 65533

May be less on some operating systems

Limited also by size of database blocks and by the DB_FILES initialization parameter for a particular instance
Database extents Maximum 4 GB, regardless of the maximum file size allowed by the operating system
Database file size Maximum Operating system dependent. Limited by maximum operating system file size; typically 222 or 4M blocks
MAXEXTENTS Default value Derived from tablespace default storage or DB_BLOCK_SIZE initialization parameter
Maximum Unlimited
Redo Log Files Maximum number of logfiles Limited by value of MAXLOGFILES parameter in the CREATE DATABASE statement

Control file can be resized to allow more entries; ultimately an operating system limit
Maximum number of logfiles per group Unlimited
Redo Log File Size Minimum size 50 KB
Maximum size Operating system limit; typically 2 GB
Tablespaces Maximum number per database 64 K

Number of tablespaces cannot exceed the number of database files, as each tablespace must include at least one file

 

source (http://download.oracle.com/docs/cd/B10501_01/server.920/a96536/ch43.htm#287916)

Oracle 9i : Max size of datafiles

February 23, 2011 8:17 am / Leave a comment


Data files are not exactly unlimited in size, so the term “Unlimited” refers to the ceiling your datafile is able to reach, and it depends on the Oracle Block Size. To find the absolute maximum file size multiply block size by 4194303. This is the actual maximum size. You may want to read the Metalink Note:112011.1.

A datafile cannot be oversized, otherwise it could get corrupted. Let’s say if your database is 8k blocks that means that one file can not exceed approximately 34GB (34,359,730,176 bytes) without having database corruption.

Sizing datafiles is a matter of manageability, it depends on your storage, the amount of space allocated in a single managed storage unit.

128G is the maximum datafile size in 10g, but considering the maximum number of datafiles a Database can have, it can make a database to potentially size 8E (exabytes = 8,388,608 T).

The maximum data file size is calculated by:
Maximum datafile size = db_block_size * maximum number of blocks

The maximum amount of data in an Oracle database is calculated by:
Maximum database size = maximum datafile size * maximum number of datafile

The maximum number of datafiles in Oracle9i and Oracle 10g Database is 65,536. However, the maximum number of blocks in a data file increase from 4,194,304 (4 million) blocks to 4,294,967,296 (4 billion) blocks.

The maximum amount of data for a 32K block size database is eight petabytes (8,192 Terabytes) in Oracle9i.

Maximum database size is 8Pb in Oracle9i & 10g (Small file Tablespaces).

Block Sz   Max Datafile Sz (Gb)   Max DB Sz (Tb)














2,048                      8              512
   4,096                     16            1,024
   8,192                     32            2,048
  16,384                     64            4,096
  32,768                    128            8,192

The maximum database size is 8Eb in Oracle 10g (Big file tablespaces).

Block Sz   Max Datafile Sz (Gb)   Max DB Sz (Tb)














2,048                  8,192          524,264
   4,096                 16,384        1,048,528
   8,192                 32,768        2,097,056
  16,384                 65,536        4,194,112
  32,768                131,072        8,388,224