3.2.1 TABLE

All data managed by DB2 is associated to a table. The data within the table is organized in columns and rows, and this represents the minimum unit of data that can be identified by the user.

The table is the main object used by DB2 applications. The SQL DML used by application programs and end users directly references data in tables.

3.2.2 TABLESPACE

A table space is used to store one or more tables. A table space is physically implemented with one or more data sets. Table spaces are VSAM linear data sets (LDS). Because table spaces can be larger than the largest possible VSAM data set, a DB2 table space may require more than one VSAM data set.

One of three different types of table spaces may be chosen for a specific table:

1.Simple (normally containing one table)

2.Segmented (containing one or more tables)

3.Partitioned (containing one, often large, table)

4.LOB (large object, new type of table space introduced with DB2 V6).

The maximum size of simple and segmented table spaces is 64 GB, corresponding to the concatenation of up to 32 data sets, each of up to 2 GB in size.

A single LOB column can be 2 GB, and the collection of all LOB values for a given LOB column can be up to 4000 TB.

Table 1 on page 12 summarizes the partition and partitioned table space sizes for different versions of DB2.

Table 1. Summary of Partition and Partitioned Table Space Sizes

DB2 Version

Number of Partitions

Maximum Size

Total Maximum Size

 

 

 

 

V4*

1 to 16

4 GB

64 GB

 

 

 

 

 

17 to 32

2 GB

64 GB

 

 

 

 

 

33 to 64

1 GB

64 GB

 

 

 

 

V5**

254

4 GB

1,016 GB

 

 

 

 

V6***

254

64 GB

16,256 GB

 

 

 

 

Note: * For a maximum total of 64 GB

Note: ** Requires LARGE parameter in CREATE TABLESPACE

Note: *** Requires DFSMS/MVS 1.5 and SMS-managed table space

Up to DB2 V4 the total maximum size of a partitioned table space is 64 GB. Starting with DB2 V5, with the introduction of the LARGE parameter at creation time, partitioned table spaces may have a total size of 1,016 GB, corresponding to up to 254 partitions each with a data set size of 4 GB.

12Storage Management with DB2 for OS/390

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IBM 5655-DB2, 5695-DF1 manual Tablespace

5695-DF1, 5655-DB2 specifications

IBM 5655-DB2 and 5695-DF1 are significant components within the IBM software ecosystem, predominantly focusing on data management and integration solutions. These offerings cater primarily to enterprise environments that require robust database management systems and associated frameworks to maintain and manipulate data efficiently.

IBM 5655-DB2 is a well-known relational database management system (RDBMS) that excels in managing large volumes of structured data. Its architecture is designed to support high availability, scalability, and performance, crucial for businesses operating in today’s data-driven world. Some of its main features include advanced indexing capabilities, support for complex queries, and dynamic workload management. Additionally, it provides strong concurrency controls, which enable multiple users to access and manipulate data simultaneously without compromising data integrity.

One of the key characteristics of DB2 is its support for various data types, including JSON and XML, making it versatile for modern applications that generate data in diverse formats. It also features robust security mechanisms to protect sensitive data, aligning with compliance standards across industries. Integration with analytics tools further allows businesses to derive insights from their data, enhancing decision-making processes.

On the other hand, IBM 5695-DF1, also known as the InfoSphere DataStage, is a powerful data integration tool that facilitates the extraction, transformation, and loading (ETL) of data from various sources to target systems. It empowers organizations to streamline their data flows, ensuring that clean, consistent information is available for analysis and operational use. Key features of 5695-DF1 include a user-friendly graphical interface that enhances developer productivity and a rich set of connectors for numerous data sources, enabling seamless data integration.

DataStage also supports real-time data integration, allowing businesses to keep their data synchronized across multiple platforms. Its parallel processing capabilities dedicatedly optimize performance, enabling organizations to handle vast datasets efficiently. It incorporates data quality tools that help in validating and cleansing data before it is used for decision-making processes.

Both IBM 5655-DB2 and 5695-DF1 are part of a broader strategy to accommodate the evolving landscape of data management. Businesses leverage these technologies to enhance their data architectures, fostering agility and competitive advantage in their respective markets. Their integration capabilities, along with a focus on security and scalability, position them as vital assets in modern enterprise environments. Whether managing critical data within a database or ensuring seamless data flow across systems, these IBM offerings provide a comprehensive approach to handling complex data challenges.