Performs the actions that you have specified in this notebook or window.
Cancels any unsaved changes that you made and closes this notebook or window.
Opens the Show SQL window.
Displays the name currently specified for the table space that you're altering. You cannot alter the table space name.
To alter another table space instead of the one you selected, click Cancel to return to the Control Center and select another table space.
Specify whether the table space is Regular, Large, System Temporary, or User Temporary.
Indicates whether the table space is SMS or DMS. You cannot alter the space management type.
A system-managed space (SMS) table space is managed by the operating system. The operating file system allocates and manages the media storage. A database-managed space (DMS) table space is managed by the database manager. A DMS table space is designed and tuned to meet the requirements of the database manager.
Specify the database partition group to which the table space belongs.
Optional: Type a comment of up to 254 characters, including embedded blanks, in this box.
Indicates the size of the pages to be used for the table space. The valid values are 4KB, 8KB, 16KB and 32KB. You cannot alter the page size.
Specify the name of the buffer pool that this table space or table space partition should reside in. If you specify an existing buffer pool, the page size of the buffer pool and page size for the table space must be equal.
Select to enable dropped table recovery if your tables contains data that must not be lost. For a dropped table to be recoverable, the table space in which the table resides must have this option turned on. Using dropped table recovery, you can recover your dropped table's data by performing a table space level restore and roll forward. This method is faster than a database level recovery and allows your database to remain available to the users.
Note: If your application creates and drops many tables in a regular table space, this may cause the table space's performance to degrade.
Select to automatically bring the table space online when the containers become accessible. A container (folder, file or disk) is accessible if the instance is up and running on the container's database partition. Since a table space can have containers defined across several database partitions, this option brings the table space online only when all the database partition instances are up and running.
Opens a window so that you can add items to the list.
Opens a window so that you can make changes to the selected item.
Removes the selected object names from the list box. The actual objects are not removed from the system.
Shows the names of containers used for the table space.
Shows the status of each container used for the table space.
For DMS table spaces, shows the type of DMS container. The type can be either File or Raw device.
For DMS table spaces, shows the size of each container in megabytes.
Shows the database partitions on which the containers reside.
For DMS table spaces, shows the stripe set to which each container belongs. You cannot alter the value shown for existing containers.
Select to add a Stripe Set column to the table so that you can view the stripe set to which each container belongs. If you want to specify a new stripe set for a container, click Add to open the Define Container window. Note: you cannot remove stripe sets once you have added them. This option applies only to DMS table spaces.
For DMS table spaces, specifies the amount of disk space allocated for this table space, which is the sum of all containers defined.
For DMS table spaces, specifies the unit size to use.
Indicates the number of pages that are written to a container before the database manager skips to the next container. The database manager uses this value to cycle through containers as data is stored.
You cannot alter the extent size.
Select to enable DB2 to update the prefetch size automatically whenever the number of containers of a table space changes (that is, after the successful execution of an alter table space operation that adds or drops one or more containers). This option also enables DB2 to calculate and update the prefetch size for the table spaces at every start-up of the database.
Specifies the number of pages that are read from the table space when data prefetching is performed. The default value is the value of the dft_prefetch_sz configuration parameter.
To change the prefetch size, use one of these methods:
Specifies an estimate (in milliseconds) of the time required by the container before any data is read into memory. This value is calculated using the following formula:
overhead = average seek time + ( ( ( 1 / rotation speed ) * 60 * 1000 ) / 2)
Specifies the time it takes to read one 4 KB page into the buffer. This value is calculated using the following formula:
transfer = ( 1 / transfer rate ) * 1000 / 1 024 000 * 4096 (assuming a 4 KB page size)