| 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 per dictionary managed tablespace |
4 GB * physical block size (with K/M modifier); 4 GB (without K/M modifier) |
| Maximum per locally managed (uniform) tablespace |
2 GB * physical block size (with K/M modifier); 2 GB (without K/M modifier) |
| Database file size |
Maximum |
Operating system dependent. Limited by maximum operating system file size; typically 222 or 4 MB 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 KB
Number of tablespaces cannot exceed the number of database files, as each tablespace must include at least one file |
| Bigfile Tablespaces |
Number of blocks |
232 (4 GB) blocks |
| Smallfile (traditional) Tablespaces |
Number of blocks |
222 (4 MB) blocks |
