ER/Studio - Embarcadero Technologies Product Documentation

USING ER/STUDIO > DEVELOPING THE PHYSICAL MODEL
• Reuse Existing File: If Use Oracle Managed Files to automatically generate Defaults is not enabled, this
option is available. If selected, lets you reuse an existing datafile, which the database manager overwrites the
first time the file is accessed.
Storage page/tab
• If the table space of an Oracle table space is dictionary managed, as specified on the Name tab of the editor, then
define the parameters of the extents on this tab.
• Specify the containers for the tablespace below: Specify an absolute or relative directory name. The relative
path is relative to the database directory. If the directory name does not exist, it will be created.
NOTE: Click Add only if you want to specify another container.
• Select a NodeGroup to assign to the tablespace: Specify either a nodegroup or a database partition number.
• Select a page size: The page size must be the same as the page size of the buffer pool that is associated with
the database.
Options page/tab
• Extent Size: Specify the number of pages that will be written to a container before writing to the next container.
The database manager cycles through the containers as it stores data. The default extent size is specified by the
database configuration parameter DFT_EXTENT_SZ.
• Prefetch Size: Specify the number of pages that will be read when prefetching tablespace data. The default
prefetch size is specified by the database configuration parameter DFT_PREFETCH_SZ.
• Overhead: Specifies the overhead, disk seek, and latency time of the I/O controller. This should be an average
for all containers belonging to the tablespace. This value is used during query optimization to determine the I/O
cost.
• Transfer Rate: Specifies the time required to read one page into memory. This should be an average for all
containers belonging to the tablespace. This value is used during query optimization to determine the I/O cost.
• Select the recovery status: If ON is selected, dropped tables in this tablespace may be recovered using the
ROLLFORWARD command with the RECOVER TABLE ON option.
Options 1 page/tab
• GBP Cache: Specifies a group buffer pool cache.
• Sizing: Specifies the settings for the different Sizing parameters:
• If you are creating a non-partitioned tablespace, enter a value between 1 and 255 in the Max rows per page
field.
• If you are creating a partitioned tablespace, enter the number of partitions you want to create for the
tablespace (between 1 and 254) in the Number of Partitions field, then select a size for the partitions from the
Partition Size (DSSIZE) list. Enter a value between 1 and 255 in the Max rows per page field.
• If you are creating a segmented tablespace, select a value from the Segment Size list, and enter a value
between 1 and 255 in the Max rows per page field.
• If you are creating an LOB tablespace, select a value from the Partition Size (DSSIZE) list.
• TRACKMOD: When set to Yes, the database manager tracks database modifications to enable the backup utility
to detect which subsets of the database pages should be examined by an incremental backup and included in the
backup image if necessary.
Options 2 page/tab
• Locking: To control concurrent access and prevent uncontrolled data access, you can create locks which
associates a database manager resource with an application, called the lock owner, to control how other
applications access the same resource. The Lock Size determines the granularity of the locks.
EMBARCADERO TECHNOLOGIES > ER/STUDIO® 8.0.3 USER GUIDE 208