Class LUWTableSpace {Analysis} derived from: SQLObject

Documentation
DB2 Universal Database SQL Reference Version 8.1 (Vol.1 and 2)
http://www7b.software.ibm.com/dmdd/library/techarticle/0206sqlref/0206sqlref.html

Table space design

A table space is a storage structure containing tables, indexes, large objects, and long data. Table spaces reside in database partition groups. They allow you to assign the location of database and table data directly onto containers. (A container can be a directory name, a device name, or a file name.) This can provide improved performance and more flexible configuration.

Since table spaces reside in database partition groups, the table space selected to hold a table defines how the data for that table is distributed across the database partitions in a database partition group. A single table space can span several containers. It is possible for multiple containers (from one or more table spaces) to be created on the same physical disk (or drive). For improved performance, each container should use a different disk. Figure 14 illustrates the relationship between tables and table spaces within a database, and the containers associated with that database.

Creating table spaces in database partition groups

By placing a table space in a multiple-partition database partition group, all of the tables within the table space are divided or partitioned across each partition in the database partition group. The table space is created into a database partition group. Once in a database partition group, the table space must remain there; it cannot be changed to another database partition group. The CREATE TABLESPACE statement is used to associate a table space with a database partition group.


IBMR DB2 Universal Database - SQL Reference Volume 1 - Version 8

Table spaces and other storage structures

Storage structures contain database objects. The basic storage structure is the table space; it contains tables, indexes, large objects, and data defined with a LONG data type.

There are two types of table spaces:
- Database managed space (DMS): a table space that is managed by the database manager.
- System managed space (SMS): a table space that is managed by the operating system.

All table spaces consist of containers. A container describes where objects are stored. A subdirectory in a file system is an example of a container. When data is read from table space containers, it is placed in an area of memory called a buffer pool. A buffer pool is associated with a specific table space, thereby allowing control over which data will share the same memory areas for data buffering.

Creation:

EXTENTSIZE number-of-pages
Specifies the number of PAGESIZE pages that will be written to a container before skipping to the next container. The extent size value can also be specified as an integer value followed by K (for kilobytes), M (for megabytes), or G (for gigabytes). If specified in this way, the floor of the number of bytes divided by the pagesize is used to determine the number of pages value for extent size. The database manager cycles repeatedly through the containers as data is stored. The default value is provided by the DFT_EXTENT_SZ configuration parameter.

PREFETCHSIZE number-of-pages
Specifies the number of PAGESIZE pages that will be read from the tablespace when data prefetching is being performed. The prefetch size value can also be specified as an integer value followed by K (for kilobytes), M (for megabytes), or G (for gigabytes). If specified in this way, the floor of the number of bytes divided by the pagesize is used to determine the number of pages value for prefetch size. Prefetching reads in data needed by a query prior to it being referenced by the query, so that the query need not wait for I/O to be performed. The default value is provided by the DFT_PREFETCH_SZ
configuration parameter.

BUFFERPOOL bufferpool-name
The name of the buffer pool used for tables in this tablespace. The buffer pool must exist (SQLSTATE 42704). If not specified, the default buffer pool (IBMDEFAULTBP) is used. The page size of the bufferpool must match the page size specified (or defaulted) for the tablespace (SQLSTATE 428CB). The database partition group of the tablespace must be defined for the bufferpool (SQLSTATE 42735).

OVERHEAD number-of-milliseconds
Any numeric literal (integer, decimal, or floating point) that specifies the I/O controller overhead and disk seek and latency time, in milliseconds. The number should be an average for all containers that belong to the tablespace, if not the same for all containers. This value is used to determine the cost of I/O during query optimization.

TRANSFERRATE number-of-milliseconds
Any numeric literal (integer, decimal, or floating point) that specifies the time to read one page into memory, in milliseconds. The number should be an average for all containers that belong to the tablespace, if not the same for all containers. This value is used to determine the cost of I/O during query optimization.

DROPPED TABLE RECOVERY
Dropped tables in the specified tablespace may be recovered using the RECOVER TABLE ON option of the ROLLFORWARD command. This clause can only be specified for a REGULAR tablespace (SQLSTATE 42613).





Parent PackageLUWAbstractNo
Export ControlPublicAccessLink Class forNone
Class KindNormalClassCardinalityn
Space ConcurrencySequential
PersistenceNo  


Operations
NameSignatureClass
getTablesList getTables ()LUWTableSpace
addEAnnotationEAnnotation addEAnnotation (String source)SQLObject
addEAnnotationDetailvoid addEAnnotationDetail (EAnnotation eAnnotation, String key, String value)SQLObject
getEAnnotationDetailString getEAnnotationDetail (EAnnotation eAnnotation, String key)SQLObject
setAnnotationDetailvoid setAnnotationDetail (EAnnotation eAnnotation, String key, String value)SQLObject
removeEAnnotationDetailvoid removeEAnnotationDetail (EAnnotation eAnnotation, String key)SQLObject
getEAnnotationEAnnotation getEAnnotation (String source)SQLObject
getEAnnotationEAnnotation getEAnnotation (String source)EModelElement
eClassEClass eClass ()EObject
eIsProxyboolean eIsProxy ()EObject
eResourceEResource eResource ()EObject
eContainerEObject eContainer ()EObject
eContainingFeatureEStructuralFeature eContainingFeature ()EObject
eContainmentFeatureEReference eContainmentFeature ()EObject
eContentsEEList eContents ()EObject
eAllContentsETreeIterator eAllContents ()EObject
eCrossReferencesEEList eCrossReferences ()EObject
eGetEJavaObject eGet (EStructuralFeature feature)EObject
eGetEJavaObject eGet (EStructuralFeature feature, boolean resolve)EObject
eSet eSet (EStructuralFeature feature, EJavaObject newValue)EObject
eIsSetboolean eIsSet (EStructuralFeature feature)EObject
eUnset eUnset (EStructuralFeature feature)EObject


Attributes
NameClassTypeInitial Value
tablespaceTypeLUWTableSpaceTableSpaceType 
managementTypeLUWTableSpaceManagementType 
extentSizeLUWTableSpaceint 
preFetchSizeLUWTableSpaceint 
overheadLUWTableSpacedouble 
transferRateLUWTableSpacedouble 
recoverDroppedTableOnLUWTableSpaceboolean 
pageSizeLUWTableSpacePageSizeTypeFOUR_K
sizeLUWTableSpacelong 
autoResizeLUWTableSpaceboolean 
descriptionSQLObjectString 
labelSQLObjectString 
nameENamedElementString 


Associations
NameMy RoleMy ClassOther RoleOther Element
--Not Named--tableSpacesLUWTableSpacegroupLUWPartitionGroup
--Not Named--tableSpaceLUWTableSpacecontainersLUWDatabaseContainer
--Not Named--tableSpacesLUWTableSpacebufferPoolLUWBufferPool
--Not Named--indexDataTableSpaceLUWTableSpaceindexDataTablesLUWStorageTable
--Not Named--LOBDataTableSpaceLUWTableSpaceLOBDataTablesLUWStorageTable
--Not Named--regularDataTableSpaceLUWTableSpaceregularDataTablesLUWStorageTable
--Not Named--tablespacesLUWTableSpacedatabaseLUWDatabase
--Not Named--LOBDataTableSpaceLUWTableSpaceLOBDataPartitionLUWDataPartition
--Not Named--regularDataTableSpaceLUWTableSpaceregularDataPartitionLUWDataPartition
--Not Named----Not Named--SQLObjectcommentsComment
=--Not Named--SQLObjectdependenciesDependency
--Not Named--objectSQLObjectprivilegesPrivilege
--Not Named--actionObjectsSQLObject--Not Named--Privilege
--Not Named--eModelElementEModelElementeAnnotationsEAnnotation
--Not Named--contentsEObject--Not Named--EAnnotation
--Not Named--referencesEObject--Not Named--EAnnotation
--Not Named--targetEndEObject--Not Named--Dependency


Generalization Relationships
NameClassSupplier
--Not Named--LUWTableSpaceSQLObject
--Not Named--SQLObjectENamedElement
--Not Named--ENamedElementEModelElement
--Not Named--EModelElementEObject



Property Settings

Data Modeler
dmItemFalseDMName 
IsTableFalseIsViewFalse
IsDomainFalseIsSPPackageFalse
Synonymns TableSpaceID 
SourceId SourceType 
CorrelationName SelectClause 
IsUpdateableTrueCheckOptionNone
IsSnapShotFalseIsDistinctFalse
PersistToServer IsPackageFalse