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This section includes the following topics:

 

■    About the Objects tab

 

■    How the Objects tab is structured

 

■    About Objects tab entities

 

 

About the Objects tab

 

This tab enables you to see objects definitions, I/O activity, and space usage over time. This section provides a general description of how to use the Objects tab in your analysis of DB2 objects. For further information on a specific DB2 object, see DB2's relevant documentation.

 

 

How the Objects tab is structured

 

The Objects tab displays information on a selected entity and its associated entities. When you open the Objects tab the selected entity is by default Database Partition, meaning that information is displayed on the Database Partition level. When you launch the Objects tab from the Activity tab with a Table or Index entity, using the launch icon, the tab is launched in context with the entity you selected in the Activity tab.

If you open the Objects tab from another tab, the historical settings (those settings which were selected when you left the tab, such as the last entity you drilled down to) are taken into account and the information displayed the last time you viewed the tab is displayed (similar to clicking the History button and returning to a previous tab).

The selected entity is always reflected in the Tab heading, which serves as a point of orientation. The highest level entity you can view information for in the Objects tab is the Data Partition level. You can select a Data Partition from the Data Partition list.

The entities displayed in the Association area are associated with the selected entity displayed in the Main area. At times, the relationship between the entity displayed in the Main area and those displayed in the Association area is that of parent to child and sometimes it merely represents that there is a relationship between the selected entity and the entities displayed in the Association area.

 

About the Main area in the Objects tab

The Main area displays overview information for the entity selected in the Association area as well as its related entity. By default, the Objects tab opens displaying information on the Database entity and its last selected related entity. You can change the database to display by selecting the desired database in the Database Partition field at the top of the Main area and its related entity by clicking the Association Control button at the top of the Association area. You can also display information on a different entity by selecting the desired entity from the Association Control button list and the related entity by selecting it from the table displayed in the Association area.

 

 

About the Association area in the Objects tab

The Association area is comprised of the Association Control button for selecting the entity whose information you want to display and a table displaying the selected entity’s related information. Two entities, Tables and Indexes, display information in two views: the Dictionary tab and the Storage & Statistics tab. The Dictionary tab displays dictionary information for this entity and the Storage & Statistics tab displays statistics based on the last runstat information for this entity.

 

 

About Objects tab entities

 

The Objects tab displays information on different entities. This section provides an overview of all entities, their meaning, and their views.

The following entities can be examined in the Objects tab:

 

■    Schemata

 

■    Tables

 

■    Indexes

 

■    Views

 

■    Database Partition Groups

 

■    Tablespaces

 

■    Bufferpools

 

■    Database Partitions

 

 

Schemata

The following table describes the information displayed for the Schemata entity.

 

Table 6-1    Schemata

 

Column    Description

Schema    Schema name

Owner    Owner name

Definer    The user who defined the schema

Creation Time    Time of schema creation

 

Tables

Two association selector options are available:

 

■    Dictionary tab- shows dictionary information for the table.

 

■    Storage & statistics tab- shows table storage information and RUNSTATS information. This is the default view. The following table describes the information displayed in the Dictionary tab.

Table 6-2    Dictionary tab

 

Column    Description

Name    Table name

Schema    Table's schema

Type    Temporary, MDC, MQT or normal

 

 

Table 6-2    Dictionary tab

 

Column    Description

Tablespace    Name of primary tablespace

Statistics Run    Date last analyzed

Range Partitioned    Yes – for Range Partitioned table

DB Partitions    The number of DB partitions this table exists in

Indexes    The number of indexes defined for this table

Logged    No or blank

Lock Mode    The Lock Mode type

Index Tablespace    Name of the tablespace which contains the indexes

LOB Tablespace    Name of the tablespace which contains the LOBs

 

The following table describes the information displayed in the Storage and Statistics tab.

 

Table 6-3    Storage and Statistics tab

 

Column    Description

Name    Table name

Schema    Table's schema

Type    Temporary, MDC, MQT or normal

Tablespace    Name of primary tablespace

Statistics Run    Date last analyzed

Pages Allocated    How many pages are allocated

Pages Used    How many pages contain actual data

Rows    How many rows

Ave. Row Len    Average row length (bytes)

Clustering Factor    The clustering factor of the clustering index (if one exists) or blank if no clustering index was defined

Extent size    Size of extent (from tablespace definitions)

% Free Pages    % Free of pages

% Overflows    % of records overflowing

Rows per Page    Rows / (# of used pages)

 

Indexes

The following table describes the information displayed in the Dictionary tab.

 

Table 6-4    Dictionary tab

 

Column    Description

Name    Index name

Schema    Index schema

 

 

Table 6-4    Dictionary tab

 

Column    Description

Table Name    Base table name

Key Columns    The number of participating columns in the index

Includes    The number of columns included in the index

Type    Clustering, Dimensions block, Block or blank for regular

Unique    Yes, No, or Primary

Columns    The list of participating columns in the index

Statistics Run    Time last analyzed

Tablespace    Name of the tablespace which contains the index

Table Schema    The table’s schema

 

The following table describes the information displayed in the Storage and Statistics tab.

 

Table 6-5    Storage and Statistics tab

 

Column    Description

Name    Index name

Schema    Index schema

Tablespace    Name of the tablespace which contains the index

Statistics Run    Time last analyzed

Clustering Factor    Clustering factor or Cluster ratio if factor is not available

Levels    How many levels exist

First Column Distincts    The number of distinct first-key values

Second Column Distincts    The number of distinct keys using the first two columns

Distinct Values    The number of distinct values

Leafs    How many leaf pages are in use

Key Length    The key length

% Deleted Rows    The percentage of rows marked ‘Deleted’

Leaf Distribution    Avg. length between leaf pages

% Empty Pages    Percentage of empty pages

% Free    Percentage of each index page to be reserved during initial index building

Extent Size    Taken from tablespace definitions

 

Views

The following table describes the information displayed for the Views entity.

 

Table 6-6    Views

 

Column    Description

View Name    View name

 

 

Table 6-6    Views

 

Column    Description

Owner    View owner

Definer    Name of view creator

Valid    Is the view valid

Text    Unformatted first N characters of view's definition

 

Database Partition Groups

The following table describes the information displayed for the Database Partition Groups entity.

 

Table 6-7    Database Partition Groups

 

Column    Description

Name    Name of the partition group

Partitions    Number of partitions in this group

Definer    Name of the user who defined the group

Create Time    Time group was created

 

Tablespaces

The following table describes the information displayed for the Tablespaces entity.

 

Table 6-8    Tablespaces

 

Column    Description

Name    Tablespace name

Type    DMS or SMS

Data Type    All, LOB, System temp or Declared temp

Bufferpool    Name of the bufferpool associated with this tablespace

Bufferpool Size    Size of bufferpool on all partitions

Page Size    Page size

Pages Allocated    Total tablespace size

Pages Used    Total tablespace used (only for DMS)

Extent Size    Number of pages per extent

Prefetch Size    Defined prefetch size or Automatic

Defined in Group    The name of the partitioned group

Overhead    DB2 internal parameter describing the overhead associated with the tablespace's disks

Transfer Rate    DB2 internal parameter, describing the time it takes to read one page

Definer    Name of the user who defined the tablespace

Remarks    User comments

 

 

Bufferpools

The following table describes the information displayed for the Bufferpools entity.

 

Table 6-9    Bufferpools

 

Column    Description

Name    Bufferpool name

Size (Pages)    Bufferpool size

Page Size    Page size of the bufferpool

Defined in Groups    Comma separated list of the DB partition groups to which it belongs

All Tablespaces Size    Size, in MB, of all tablespaces associated with this bufferpool

Tablespaces    The number of tablespaces defined to use this bufferpool

 

Database Partitions

The following table describes the information displayed for the Database Partitions entity.

 

Table 6-10    Database Partitions

 

Column    Description

Server    Server name

ID    ID of the partition

Default on Server?    Yes if this is the default partition when connecting to the database on that machine

Total Memory    Total shared memory dedicated for this database partition

Total Bufferpools Size    Total shared memory dedicated for this partition's BPs

Defined in Groups    Comma separated list of DB partition groups in which this DB partition participates

 

 

 

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