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 2 22-1 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 20,00 0 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 |
2 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 2 22 or 4 M 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 LOG_FILES initialization parameter or 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 |