log RBA (or LRSN) of updates to a table space. The record is opened when a first update is detected, and closed after an interval of read only activity. The interval is defined with two read-only switch parameters on the DB2 installation panel

DSNTIPN.

3.5 DB2 Application Table Spaces

All application data in DB2 is organized in the objects described in 3.2, “DB2 Data Objects” on page 11. Application table spaces and index spaces are created as shown in 3.3, “Creating Table Spaces and Index Spaces” on page 13.

Application table spaces and index spaces are VSAM LDS data sets, with exactly the same data attributes as DB2 system table spaces and index spaces. The distinction between system and application data is made only because they have different performance and availability requirements.

3.6 DB2 Recovery Data Sets

In order to ensure data integrity, DB2 uses several traditional data sets for recovery purposes. Not all of these are always needed by DB2, but all of them are required for contingency reasons. DB2 supports two or more copies of these data sets to ensure a high level of data integrity.

A short description of DB2 recovery data sets is provided here. A good description is available in "Managing the Log and the Bootstrap Data Set" in the Administration Guide of DB2 for OS/390, SC26-8957. An attempt has been made to avoid redundancy in these descriptions.

3.6.1 Bootstrap Data Sets

DB2 uses the bootstrap data set (BSDS) to manage recovery and other DB2 subsystemwide information. The BSDS contains information needed to restart and to recover DB2 from any abnormal circumstance. For example, all log data sets (active and archive) are automatically recorded within the BSDS. While DB2 is active, the BSDS is open and is updated.

Because the BSDS is critical for DB2 data integrity, DB2 always requires the presence of two copies of the BSDS at start up time. If a copy fails while DB2 is running, DB2 sends a warning message and continues operating with a single BSDS. It is the responsibility of operations to monitor this circumstance and restore the BSDS duality as soon as possible.

To recover a lost BSDS, when DB2 is executing:

1.The failing BSDS must be deleted.

2.The failing BSDS must be redefined, or alternatively, an existing spare BSDS copy must be renamed.

3.The BSDS is rebuilt with a -RECOVER BSDS command.

If a BSDS copy fails while DB2 is starting, the startup does not complete.

To recover a lost BSDS, when DB2 is stopped:

1. The failing BSDS must be deleted.

DB2 Storage Objects 17

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IBM 5695-DF1, 5655-DB2 manual DB2 Application Table Spaces, DB2 Recovery Data Sets, Bootstrap Data Sets, Dsntipn
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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.
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