tablespaces

It is not always possible to have the same tablespaces set up in test that you have in production.

As well as a table can be moved between tablespaces within a database, a table can be moved between two different databases.

The same is true for temporary tablespaces often used for performing sort operations.

When specifying this NONRECOVERABLE keyword, the user is not forced to take backups of the tablespaces immediately.

perl tbs_usage. pl - This script provides the free and used space for all the tablespaces for a given database.

Use SMS or DMS file tablespaces, which may allow operating system caching to negate some of the performance degradation.

Views, triggers, and stored procedures reside in tablespaces, as well.

All of the tablespaces, except small_tables, are defined against the same set of disk drives.

Individual tablespaces are recommended for each table identified previously, for management efficiencies.

DBAs have the option to choose the type of the tablespaces required for the catalog, and for temporary and user tablespaces.

DB2 also supports partial de-clustering, where tables and tablespaces can be spread across a subset of the available partitions.

With DMS tablespaces, DB2 has more control over how data pages are physically mapped in disk space groupings known as extents.

All storage components of the DB2 database were defined on this volume group, including tablespaces, log, and backups.

Ensure that there is sufficient free space on the system catalog and the system temporary tablespaces.

TABLESPACE_MAP The user may specify tablespace name mappings to be used instead of the tablespaces from the source system during a copy.

For DMS device container tablespaces, the operating system does not cache pages in the file system cache.

For optimal database performance, it is critical to have tablespaces defined properly.

Review the tablespaces where the indexes are to be stored.

Review the tablespaces where the objects are to be stored.

The SYS_ANY keyword can be used for all tablespaces.

Of course, this also requires that you create separate tablespaces for data and indexes.

Note: The Segment Advisor does not evaluate undo and temporary tablespaces.

The strategy is to spread the data for all tablespaces across as many drives as possible to maximize the IO parallelism.

What are the wags tablespaces can be managed and how do they differ?

IBMDEFAULTGROUP - default database partition group for the tablespaces containing the user tables.

You have already extracted DDL and made the required manual changes for the mapping between tables and tablespaces if required.

It is recommended for database managed tablespaces to split regular data from LOB data, placing LOB data in a large tablespace.

As a rule of thumb for OLTP applications, use DMS tablespaces with multiple devices.

Spreading tablespaces over multiple containers (which map to separate disks).

Temporary and catalog tablespaces must be placed SMS.

The tablespaces were defined carefully to ensure excellent disk performance.

The following example illustrates how database administrators can create a database using both DMS and SMS tablespaces.

The disk subsystem is organized for optimal performance by carefully mapping the tablespaces onto the disks.

In addition, the user can specify specific mappings for some tablespaces, and the default tablespace selection algorithm for the remaining.

Restriction on Renaming Tablespaces : You cannot rename the SYSTEM or SYSAUX tablespaces.

IBMTEMPGROUP is - default database partition group for system temporary tablespaces.

Note: In AIX you can only use JFS for SMS tablespaces.

The multipage_alloc is used for SMS tablespaces only, and it is used to improve insert performance.

In the database, five regular tablespaces and one temporary tablespace are defined.

This way, a LOAD FROM CURSOR is a fast and easy possibility to move data between different tablespaces or different databases.

After the database is created, you can define additional system temporary tablespaces, user tablespaces and buffer pools.

By executing the DB2 command LIST TABLESPACES, you can see all the tablespaces of a database.

If you are using DB2 automatic storage, you need to decide whether you want Performance Expert to collect counters for tablespaces.

DB2 EEE supports two types of tablespaces: system-managed space (SMS) and database-managed space (DMS).

Depending on the table type being used, MySQL stores data in either single files, multiple files, or tablespaces.

And restores them to the original schema using default tablespaces.

This can be verified by executing a query against the DB2 catalog views SYSCAT. TABLES and SYSCAT. TABLESPACES.

You should understand the basic concepts of tablespaces, tables, and columns.

For production machines, we recommend to choose the appropriate database elements like tablespaces and so on.

This option is available for all DB2 tablespaces, including system and temporary tablespaces and database managed tablespaces.

Tablespaces that have a lower sequentiality ratio also are better candidates for SSDs.

In this benchmark, a moderate page size, 16KB, was chosen for all DMS tablespaces.

With contiguous data pages, DMS tablespaces allow for much more efficient operations such as sequential table scans than SMS tablespaces do.

This is the layout for database partition groups, buffer pools and tablespaces.

In DB2 versions prior to 9. 1, tables were often moved between tablespaces because the maximum size of a tablespace was reached.

With DB2, you can put index, data in separate tablespaces.

With DB2 9. 7 you can also convert your database and tablespaces to use automatic storage after database creation.

Here are some tips when setting up database and tablespaces.

You can choose different page sizes for the different tablespaces based on the type of the application that is used.

If you use the defaults when creating a database, the following system-managed tablespaces are created

DB2 does not need a list of tables for taking backups of DMS tablespaces, and

At any time, administrators can create more tablespaces using, for example, the commands shown in

Here is a sample output of the db2 list tablespaces command showing the tablespace state

TABLESPACES list of tablespaces to transport

The following table shows the details of all tablespaces