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Issue April 2009

BS2000/OSD

SESAM™/SQL-Server

The SQL Server for BS2000/OSD

Pages 12

The SESAM™/SQL-Server database system combines the advantages of the relational model with all the features expected for running business-critical online applications.

It provides the relational database language SQL (Structured Query Language) for data access. SESAM™/SQL-Server is based closely on the current standard ISO/IEC 9075:2008.

SESAM™/SQL-Server can be accessed from arbitrary platforms, by clients as well as by browser: via embedded SQL, ODBC and JDBC interface. The APACHE webserver includes a separate interface for SESAM™/SQL-Server.

Special techniques guarantee optimum performance and scalability: 64bit addressing, multitasking and multithreading, partitioned tables, database cache, group commit and asynchronous commit, data compression.

Advanced availability features permit fault-tolerant 24-hour operation.

Sophisticated self management features – e.g. self-managed access plans, automatic adjustment to different workloads, and automatic extension of DB limits on demand – minimize DB administration overhead and help keep down operating costs.

Contents

1 Introduction 2

2 BS2000/OSD: The platform for database systems 2

3 SESAM/SQL-Server 3

3.1 SQL2008 standard 4

3.2 High levels of performance and scalability 4

3.3 Permanent availability and high level of security 7

3.4 Comprehensive data protection 7

3.5 Manageability 8

3.6 Accessibility 10

4 The integrated OLTP system: SESAM/SQL-Server and openUTM 11 5 Overview of the new features offered by SESAM/SQL-Server V6.0 12

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1 Introduction

Database systems (DB systems) are now an integral part of information processing. They alone make it possible to implement secure, consistent and integrated information management. Database systems offer many advantages:

„ Rapid access to information

DB systems provide the user with a quick and easy-to-use means of retrieving information of all kinds in both online transaction processing (OLTP) applications and in end-user computing. OLTP refers to a number of users accessing the same programs and data online. The transaction security guarantees that all of the changes of data within a transaction are either completely done or none of the changes is done. Support for the standardized database language SQL makes it easy for users to create their own applications or to use standard applications.

„ Avoidance of data redundancy

DB systems make it possible to avoid storing the same data more than once or storing inconsistent data.

„ Protection of data against misuse and loss

DB systems offer effective data protection functions that ensure that users can only access data for which they have the required authorization. Should a crash occur, sophisticated recovery concepts enable the data to be reliably reconstructed on the basis of backup copies and change logging.

„ Dynamic information posting on the World Wide Web

Web applications that are not limited to static web pages require database systems in order to save dynamic content. Only in this way is it possible to manage dynamic information economically.

„ Support for business-critical computing

Companies today must be in a position to provide optimum support for their processes and to guarantee their web solutions, by providing secure access to business-critical information. High-performance database systems providing high levels of availability and scalability make a considerable contribution to this.

2 BS2000/OSD: The platform for database systems

Large-scale OLTP and database applications make special demands on the system architecture if it is to be used as the platform for database systems:

„ a high level of extensible computing power to ensure short response times

„ the ability to store large amounts of data and access this data quickly

„ a high level of reliability and availability

„ an efficient backup procedure

„ convenient and (largely) automated system administration

„ powerful transaction monitors for OLTP applications

„ the ability to perform large-scale standard tasks batch processing

The architecture of the BS2000/OSD systems perfectly meets all these demands. The reason why this is so can be found in the history of this architecture. Since general-purpose computers were originally the mainstay for all data processing tasks to be performed within a company or organization, processor concepts for dynamic load distribution (SMP), high-capacity mass storage, efficient backup media, procedures for increasing reliability, administration tools, and powerful transaction monitors were developed very early on.

With these features, which have been tried and tested over a long period of use, BS2000/OSD systems were predestined for use as database servers, particularly for running business-critical applications.

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3 SESAM/SQL-Server

SESAM/SQL-Server is used by several hundred thousand end users throughout the world and is one of the leading database systems on mainframes today.

SESAM/SQL-Server is a database system that combines the advantages of the relational data model with all the features you would expect from a high-workload production system. The system therefore offers tabular data structures, which are easy to comprehend, handle and manipulate. It is also suitable for high transaction rates and large amounts of data and offers impressive security and availability features. Backup procedures ensure reliable round-the-clock operation. Thanks to its multitasking architecture, SESAM/SQL-Server can be very effectively scaled on multiprocessor systems.

The add-on ODBC and JDBC interfaces mean that it also supports database access from Windows and JAVA applications (also on the basis of Enterprise JavaBeans (EJB)). As well as this, the APACHE webserver in BS2000/OSD offers its own interface to SESAM/SQL-Server. The scripting language PHP (Hypertext Preprocessor) can be used to query and modify SESAM/SQL databases.

The particular strength of SESAM/SQL-Server lies in its use in OLTP applications. Numerous SESAM installations currently exist in which several thousand users access the same data simultaneously. Some of the administered databases are several terabytes in size and contain up to 300 million records per table. SESAM/SQL-Server thus offers an infinite range of potential applications. The user is secure in the knowledge that even a dramatic increase in the amount of data to be stored or the number of users presents no problem for SESAM/SQL-Server.

Web applications must be available round-the-clock and must also be flexible enough to handle unexpectedly high workloads. The success of business critical web solutions is very dependent on the reliability and scalability of the data server used. And reliability and scalability are the main strengths of Server. Used in conjunction with BS2000/OSD, SESAM/SQL-Server provides a high-performance data server for business-critical solutions.

SESAM/SQL-Server provides daily evidence of its capability in the field of business-critical computing. For example, it is used by customers such as the German Kraftfahrt-Bundesamt, the Swedish Labor Exchange and Siemens IT Solutions and Services, with more than hundred thousand users regularly accessing the data server. In conjunction with its high level of reliability and almost unlimited scalability, SESAM/SQL-Server is able to provide a convenient web connection (see section 3.6

“Accessibility”).

SESAM/SQL-Server runs on all BS2000/OSD systems and can be used as a data server by arbitrary platforms. The following features make SESAM/SQL-Server the ideal choice for this task:

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3.1 SQL2008 standard

Although almost all relational database systems use the SQL query language (Structured Query Language), the process of porting applications written for a particular DB system to a different DB system used to involve a great deal of time and effort. The main reason for this was the disparity between the various SQL dialects. This led to the formula-tion of rules and standards by independent bodies. SESAM/SQL-Server is based closely on the current standard ISO/IEC 9075:2008. This guarantees a high level of portability SQL applications. SESAM developers ac work within the DIN standardizing body on standardizing SQL. They are thus ensuring SESAM/SQL’s standard-complian

of tively

t further

jects of up to 2 GByte (BLOBs) in

HAR and NVARCHAR data types enable Unicode characters to be stored in SQL tables and to be processed using SQL

vides greater security, especially in business applications in which a very large number of PCs access production databases.

jects (BLOBs). BLOBs are required for storing multimedia data

s data is becoming more and more important.

siness and multimedia data. All this is offered together with transaction security and the backup mechanisms of the DB system.

ty in the form of BLOBs. SESAM/SQL-Server provides suitable function calls for reading and writing XML

ML parser nd a DOM interface. Thus existing database applications based on openUTM can be adapted to XML very easily.

se system which enables the building of large-scale databases and OLTP applications nters means that greater

each other. A distinction is made between two basic task types: OLTP applications and Online Analytical Processing

mber of read and write statements. This involves repeating a small number of different

.g. for statistical analyses. This frequently development.

In addition to the basic SQL operations of standard SQL, SESAM/SQL-Server contains important extensions to Core SQL as defined

by the SQL standard, such as multiple columns and operations to store and retrieve large ob SQL tables.

A new SQL feature permits the use of external files in CSV format as SQL tables in FROM clauses. The NC

tools.

The SQL standard defines extended rules for ensuring data consistency (e.g. referential integrity, check clauses), which are also supported by SESAM/SQL-Server. This means that SESAM/SQL-Server pro

Binary Large Objects (BLOBs) for multimedia SESAM/SQL-Server supports the use of Binary Large Ob content, i.e. for text, graphics, images, sound and video.

Managing the data of an IT transaction takes on vital importance in the increasingly open IT market. In particular, the storage of unformatted, multimedia data in combination with traditional, formatted busines

BLOBs, as storage elements in a database, provide the crucial basis for this.

By storing, reading and updating BLOBs in the database jointly with the general structural data of an IT transaction, the user always has a common interface for all bu

XML support

XML is not only becoming more and more important for web applications, but is also acquiring growing significance as a document exchange format between applications and database. SESAM/SQL-Server supports the storage of XML documents in their entire

documents.

Generating XML documents from existing SQL tables and mapping XML documents to SQL tables is offered as WebRowSets on the JDBC interface. This can also be realized in pre-database components. To this purpose openUTM offers an X

a

3.2 High levels of performance and scalability

SESAM/SQL-Server is a relational databa supporting very large numbers of users.

The increasing use of web applications and the concentration of applications in fewer computer ce demands are made on databases – demands that are satisfied by SESAM/SQL in every respect.

A data server for this type of application scenario must be able to execute different types of tasks quickly, without these tasks inhibiting

(OLAP).

„ OLTP applications

In OLTP applications, a large number of users access the same databases and application programs. Examples of such applications include order processing systems, accounting systems, and inventory management systems. OLTP transactions normally comprise a relatively small nu

transactions a great number of times.

„ Online Analytical Processing (OLAP)

With OLAP, very complex queries are often submitted to the database system, e entails reading large volumes of data and performing extensive data analysis.

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itectur e of web ap

bility, dynamic

es, , shared SQL, shared record locks, block mode, data

n.

k family with up to 16 BS2000 tasks. This lets the DBH use all the system’s available

dicate, the Enterprise Edition of SESAM/SQL offers optimal scalability in accordance ith the RPF value of each system.

to the applic ith. of a single system image.

hows the system

considerable increase in throughput. It d complex

tems or evaluation programs). Replicates of original

ly applications.

xists for this, and the working set in the buffer Storing the data redundantly serves to increase the level of availability. A failure of the original session does not prevent

ations from accessing other computers.

ssing

is forming a bottleneck, especially in web applications, OLAP, data mining and OLTP applications with strong Parallelization functions and other arch

important precondition for the us

al features ensure that complex queries do not disrupt OLTP operation. This is an plications, in which the data server often has to cope with widely varying load profiles.

The most important technologies and functions are described below:

„ Functions which enable parallel processing,

e.g. multitasking (scala

load distribution), multithreading and replicate databases.

„ Techniques for especially efficient use of system resources,

e.g. 64bit addressing, partitioned tabl cost-based optimizer

compressio

„ Support of very fast storage media, e.g. global storage.

Multitasking

The Enterprise Edition of SESAM/SQL allows the DBH to be loaded as a tas

processors to cope with the application load. SESAM/SQL-Server handles the load balancing task independently and makes fine adjustments to suit the load situation.

As the results of the various benchmarks in w

The system architecture is invisible how many tasks it currently has to deal w itself by means

ations. In other words, they direct their SESAM jobs to the DBH regardless of Also, as far as the administrator is concerned, the multitasking family represents

The figure right s

architecture of the Enterprise Edition of SESAM/SQL:

Multithreading

Multithreading architecture enables the SESAM database handler (DBH) to process jobs in parallel, thus making use of time in which jobs wait for the completion of I/O operations (e.g. write and read accesses to disk). The processing of a different, executable job is activated for the duration of the I/O operation. This results in a

also allows long-running an

database queries (OLAP) to be processed partition by partition without impeding OLTP operation.

Replicate databases

Applications often have read-only access to databases (e.g. information sys

databases can be created on a supplementary DBH for such applications. The database administrator can update the replicate databases as and when required.

Replicate databases offer a number of significant advantages:

„ Live operation is not impaired by the locks of the read-on

„ If the replicates are processed by a separate DBH, a separate DB buffer also e

of the original DBH is not destroyed. The replicates can also be processed by several DBHs concurrently.

„

read-only applic

„ Work processes are no longer dependent on a centralized computer system.

„ A replicate database can be used with shadow databases to repair a failed original database very quickly. 64bit adre

The 64bit main storage database can keep large amounts of data resident in memory. This is useful in any case where the phys. I/O

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ments. The 64bit main storage database facilitates a significant reduction of the „elapsed time“ by saving

arge database tables can be partitioned into a number of spaces. The splitting may be performed by way of primary key values (BLOB tables). The splitting is transparent to the applications. The partitioning of a large table into a

e

he cost-based optimizer ensures that a particularly efficient access plan is created, in which as few system resources as ed (CPU time, I/O accesses etc.).

he s av

ser (shared SQL). This can eliver a significant boost to performance,

lications in which

ther transactions can still read this duces the number of locks

p to 50% of the commands. The saving is even greater in the case of simple statements.

is therefore easy to

ues in only a few records

isk accesses

r, a ss. For storage media were developed for the BS2000/OSD systems.

r che, thus dramatically ducing the number of write and read accesses performed on disc. This greatly increases overall performance, even in comparison with disc cache.

By means of a several other techniques such as database caching, buffering, asynchronous I/O, and group commit, read and write operations to the disks are reduced to a minimum.

Large I/O transfer sizes (64 – 160 KB depending on the disk type) are used as much aspossible. response time require

phys. I/O.

The 64bit addressing is implemented for the primary and the secondary data buffer. Thus both together can be extended up to 48 GB.

Partitioned Tables L

or by a hashing algorithm

number of smaller units reduces the necessary backup and recovery times. If a partition failes, the remaining partitions ar available furthermore.

Cost-based optimizer

When an application issues an SQL statement, an access plan is created. This plan describes the type and order of the individual evaluation steps of the SQL statement.

T

possible are us

Different SQL formulations which have t access plan. Thus, programmers do not h Shared SQL

The optimized access plan is stored in main memory and can be used by more than one u

ame function are recognized by the optimizer and therefore have the same optimum e to determine the best formulation themselves.

d

especially in OLTP app

certain processing steps are constantly repeated.

Shared record lock

An increase in the transaction rate is also achieved by an extended locking concept. If a read access is executed on a record, this record is normally locked to other transactions. With a “shared record lock”, o

record. This re

and allows more parallel transactions to be executed. This also makes it possible

start complex and long-running queries without interfering with parallel OLTP operation. to

Block mode

Data records can be collected or inserted in blocks. With a typical SQL statement of medium complexity, for example, this produces a saving of u

Data compression

Data is automatically compressed when it is stored and thus requires less storage space. Compressing data to significant attribute values enables a database to be created to meet maximum requirements.

It

„ define attributes for which there are val

„ maintain attribute definitions even if there are no more attribute values for these definitions.

The fact that the compressed records are shorter and therefore occupy fewer storage blocks means that data can be accessed more rapidly. It is also possible to keep more records in main memory, thus reducing the number of disk accesses.

Optimization of d

The performance of a DB system is not determined solely by the power of the processor. In database systems in particula large number of read and write accesses to disk are performed which are relatively slow compared to main memory acce this reason, exceptionally fast

Global storage (a battery-backed semiconductor storage device), for example, provides an access time that is 2000 times faste than hard disks.

SESAM/SQL-Server combined with DAB (Disk Access Buffer) can use global storage as a data ca re

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3.3 Permanent availability and high level of security

The availability demands being made on business critical applications are increasing all the time. A system failure in many of today’s companies and organizations can result in production operation coming to a virtual standstill. 24-hour operation is required especially for globally accessible web applications if databases have to be accessed round-the-clock across the various time zones.

As a result, the following is required of a high-performance data service:

„ Backup systems must be started automatically in error situations.

„ The bulk of maintenance operations must be performed during normal operation.

In this regard, SESAM/SQL-Server provides a number of functions which allow it to satisfy these requirements. Availability of partitions of a database table

A database table can be splitted into several partitions. If a partition failes, the remaining partitions are available furthermore. Applications which do not work with the failed partition can go on running on the database table uninterruptedly.

Replicate and shadow databases

An original database or a section of an original database can be replicated for use by read-only applications.

This increases availability because the read-only applications using the replicate under a separate DBH are not affected in the event of a failure of the original database session.

The replicate database can also be used to repair failed original databases very quickly: the replicate can be run as a shadow database in parallel with the original, which means that only a few after-images need to be applied if the original database fails. Support for TimeFinder functionality

To minimize the effects of the creation of database backups on current database operation, SESAM/SQL-Server supports the TimeFinder functionality of EMC’s Symmetrix disk systems. This means that backup copies can be created by splitting a disk mirror.

Shortening the restart time

SESAM/SQL-Server version enables OLTP operation to start already in the course of a restart, and includes an option for controlling the restart duration.

Automatic extension of DB limits

If the physical limits of the database prove to be too confining during a database session as a result of extensive additions and updates, they are extended automatically in the session. Since the extension is performed online, availability is increased considerably.

Online data definition and utilities

SESAM/SQL-Server allows database administration to be performed online. All database administration tasks can be performed during the online session. This means new databases can be created and the schemas of existing databases changed online (Online DDL = Online Data Definition Language). The reorganization of a single table of a space can be performed parallel to the database operation.

Tasks such as importing and exporting tables and backing up and recovering databases (applying updates) are performed during normal online operation, i.e. the database does not have to be deactivated. It is possible to use HSMS as well as ARCHIVE to create tape backups.

Space concept

SESAM/SQL-Server derives the internal database schema (which describes the physical structure of the database) from the logical database schema.

However, this standard procedure does not cover all special requirements regarding access methods, processing types and data volume. The storage structure language (SSL) allows users to optimize the organization of storage space in accordance with their specific requirements, thus enabling them to accelerate access to the data or to control storage resources.

The entire database does not need to be deactivated if users wish to carry out this type of optimization or wish to reconstruct defective parts of the database. The physical database structure provided by SESAM/SQL-Server makes it possible to limit deactivation to the individual parts (i.e. spaces) involved.

3.4 Comprehensive data protection

Wherever large amounts of data can be accessed directly, appropriate measures must be taken to protect this data from unauthorized access. In the case of SESAM/SQL-Server, this can be achieved through a password-based access protection mechanism, which extends down to field value level. Passwords can be assigned to ensure that users can only access the data that they need to carry out their particular tasks. SQL access protection allows a distinction between rights granted to users and rights granted to user groups. In conjunction with the openUTM transaction monitor, passwords can be assigned not only to data but also to applications and procedures. The database handler supplies the SECOS Security Audit Trail (SAT) with events relevant to data security.

The data values of selected columns can be stored encrypted with the standard algorithm AES (Advanced Encryption Standard).

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3.5 Manageability

Large-scale database applications require a convenient means of managing the database system so that the administrator can handle a large and ever-increasing number of administration tasks without difficulty. SESAM/SQL-Server therefore offers numerous functions which provide support to the administrator. Everything the administrator needs is included in SESAM/SQL-Server – from performance monitor, through utility monitor, to toolbox containing sample procedures, templates and special administration tools. This administration pack is included free with SESAM/SQL-Server. The utility monitor and performance monitor administration functions and session administration can be controlled via a browser interface.

Performance monitor

SESAM/SQL-Server includes a performance monitor, which provides the administrator with information on the utilization of SESAM resources (e.g. CPU and disk accesses).

Performance monitor data can also be edited graphically. This allows the database system to be tailored to the application involved. The outputs can be routed to an SNMP agent. This permits online evaluation and monitoring of database operation in the SNMP network, with the possibility of using any vendors’ management platforms.

In addition there exists a connection to the BS2000/OSD peformance monitor openSM2 (as of V8.0) for the display resp. graphical presentation of the statistical data.

Utility monitor

To allow convenient execution of database administration tasks, DDL and utility functions can also be initiated online via screen forms, in addition to ESQL programs.

The actions can be logged in a file, which can be processed in dialog as well as in batch mode. The latter is advantageous for automation of recurrent administration tasks.

Importing and exporting tables

To transfer data as quickly as possible from one database to another, a table (e.g. from a backup copy) can be mounted into another catalog with the appropriate metadata changes. The catalog into which the table is to be mounted may be located on another DBH or even another computer altogether.

Self management

Sophisticated self-management features minimize DB administration overhead and so keep a lid on operating costs. For example, a cost-based optimizer calculates the resource consumption of potential access plans and selects the most

economical one. SESAM/SQL-Server generates the access plans dynamically and so offloads programming and organizational tasks from the administrator. The multitasking/multithreading architecture automatically handles dynamic adjustment of the system to different workloads. The DB limits are automatically extended as necessary.

SESAM/SQL-Server offers in terms of self management furthermore: Self-configuring

SESAM ONLINE backup with HSMS / Concurrent Copy with BCV

The mutually coordinated collaboration between SESAM/SQL, HSMS and the EMC2’s BCV technology for Symmetrix disk systems is an impressive example of self-configuring. It shows clearly how the complexity of IT systems can be efficiently managed and added value created through reduced complexity.

The increasing size of data resources, the growing number of users, and the trend toward round-the-clock operation is

presenting many companies with this logistical challenge: it takes longer and longer to produce the database copy in the case of large databases; at the same time the time window in which maintenance and backup work can be carried out without disrupting end users is shrinking.

With SESAM/SQL-Server and HSMS backup work can be carried out fully automatically with no disruption to online operation. Users no longer have to struggle with the logistical problems of narrow time windows and need not concern themselves with coordinating the software and peripheral components involved. The database administrator only has to initiate execution of a single COPY statement to back up BCV mirrors to an HSMS archive. This causes SESAM to copy the required database online in collaboration with HSMS, by means of a BCV mirror. At the same time a CHECK utility can run on the database files

concerned, ensuring that a copy checked on formal consistency is stored in the HSMS archive.

In combination with HSMS V8.0 and BS2000/OSD-BC V7.0, SESAM/SQL also provides use of the HSMS backup of TimeFinder/Clone that is integrated into the DB backup functions.

When backing up BCVs, the BCV mirror of a remote data set managed via SRDF can also be used instead of a local BCV mirror.

Corresponding to this Symmetrix support, SESAM/SQL, in combination with HSMS V9.0 and BS2000/OSD-BC V8.0, also provides use of the HSMS backup of SnapView Clone for FibreCat CX disk systems that is integrated into the DB backup functions.

Self-optimizing

SNMP support by SESMON Performance Monitor

SNMP makes it possible to define and display critical statuses and automatically launch responses as demanded by the “autonomic cycle” of an autonomous system. A special SNMP subagent for SESAM/SQL supplies the SNMP master with SESAM performance monitor data of ongoing operation. This permits online evaluation and monitoring of database operation in the SNMP network, with the possibility of using management platforms from any vendors. An SNMP subagent collects the SESAM performance data. This is the basis for using any vendors’ SNMP management platforms.

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Self-protecting SAT support

SESAM/SQL-Server supplies the SAT (Security Audit Trail) subsystem of the product SECOS with events relevant to data security. This subsystem serves to provide an audit trail and supports selective logging of events relevant to data security in specially protected files (SAT logging files). By evaluating these files appropriately authorized users are given an overview of major interventions affecting actual database operation (such as administration and utility accesses, changes to rights, manipulation of the data structure). This makes security easier for SESAM users and facilitates auditing. In addition to the logging function, SAT offers an ALARM function. The security coordinator has the option of defining conditions that will trigger an alarm when certain events are invoked. If an alarm is triggered, a message is displayed on the main console and the event is additionally written to the logging file.

SECOS and GUARDS

SESAM/SQL-Server supports the GUARDS mechanisms of SECOS (use of co-ownership of the DMS), thereby allowing the restriction of administration rights for the databases on different IDs.

Because of its highly advanced autonomic system behavior, SESAM/SQL-Server has significantly lower operating costs than comparable DB systems.

A typical example:

A large user operates applications with SESAM/SQL-Server on BS2000/OSD and similarly large applications with a database system from a different mainframe manufacturer. Six employees are required for administration of this database system, compared with 1.5 employees for administration of SESAM/SQL-Server.

High level of flexibility

SESAM/SQL-Server was conceived as a relational database system from the very beginning, which accounts for its great flexibility in data storage and maintenance.

Multi-database operation

A SESAM database handler (DBH) can process up to 254 databases in parallel. This allows each application program to access several databases concurrently.

Any number of tables may be created in each database. A table can comprise over 25,000 columns (attributes), which provides numerous possibilities for structuring the data (database and table level). Multiple joins between tables conforming to the SQL standard are also possible.

A database can be subdivided into max. 400 spaces (files), each of which can contain up to 32,000 tables and indices. A space is the smallest backup unit.

Spanned records

The length of the records to be stored is not limited by the size of a physical database block. A record may extend over multiple blocks (spanned record), which effectively means that there are no limits on its length.

Multiple columns

SESAM/SQL-Server permits the use of multiple attributes. Up to 255 attribute values for a multiple attribute can be stored in a single record. This enables the number and complexity of tables (number of columns) to be reduced to a minimum.

Distributed database system with SESAM/SQL-DCN

The add-on product SESAM/SQL-DCN makes it possible to process databases located on different servers in a single user session.

This means that the data can be stored on the server on which it is most frequently required.

Distributed data storage is important, for example, whenever certain parts of an organization or public authority (e.g. production, accounting, marketing, branch offices) are spread over different locations, or the data is to be stored on different servers. Here, uniform data management between central host systems and decentralized systems can be realized. This allows the structure of the organization to be reflected in the way in which the data is stored.

Advantages of distributed data storage with SESAM/SQL-DCN:

„ Flexible organization:

Work processes are no longer dependent on a centralized data center.

„ Higher level of availability:

If one server fails, it does not mean that the whole system fails.

„ Higher performance level:

The processing of user requests on various servers results in an increase in throughput. SESAM/SQL-DCN provides the following important functions for processing distributed data:

„ Distribution transparency:

The location of a database is totally irrelevant to the application program. It is determined internally by the system. Consequently, application programs remain unaffected by the introduction or modification of data distribution.

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„ Two-phase commit protocol:

The two-phase commit protocol ensures network-wide transaction management. A lost connection causes all open transactions to be reset on all the servers involved.

„ Deadlocks and longlocks:

Deadlocks and longlocks are recognized and resolved by the system beyond the boundaries of a single server.

3.6 Accessibility

ESQL

SQL applications can be created under COBOL using the SQL precompiler ESQL-COBOL (BS2000/OSD).

SESAM CALL-DML

The SESAM CALL-DML interface is offered in parallel with the ESQL interface. ESQL statements can also be used in a CALL-DML transaction. DRIVE

DRIVE is a fourth-generation programming language (4GL). It combines great ease of use with powerful language tools, enabling substantial productivity gains to be achieved in the development process. Remote PC access with ODBC

SESAM/SQL-Server supports the Microsoft-defined ODBC (Open Database Connectivity) interface, which allows Windows applications to communicate with database systems. The CD-ROM supplied with SESAM/SQL-Server includes a demo version of the partner product ODBC-Rocket. ODBC-Rocket, developed by gfs in Hamburg, provides an ODBC interface for

SESAM/SQL and additionally supports UDS/SQL, LEASY and ISAM. Java programs: JDBC interface of SESAM/SQL-Server

JDBC stands for “Java Database Connectivity” and is the standard call-level interface used by Java programs to access SQL databases. Database-independent Java applications can run with SESAM/SQL-Server via the JDBC interface. This means that Java applications available on the world market can also be used with SESAM/SQL-Server.

The required JDBC driver is included in SESAM/SQL-Server and is supplied on CD-ROM together with SESAM/SQL-Server. The JDBC driver is offered free of charge, or you can download the driver directly from our web server.

SESAM/SQL-Server provides the JDBC interface on the basis of JDBC2 technology. It is a Type 4 driver, i.e. “native-protocol fully Java technology-enabled driver”. The advantage of this over other types, such as “ODBC/JDBC bridges” and “partly Java technology-enabled drivers”, is that no binary code needs to be installed on the client machine.

The use of BLOBs is also supported at the JDBC interface of SESAM/SQL-Server. Connection pooling

SESAM/SQL-Server allows to use a client/server connection for more than one session one after another. This is useful if the JDBC client is part of an application server, working with several connections in parallel. Thus the necessary Java classes do not have to be reloaded and the TCP/IP connections don’t have to be reconstructed either.

APACHE Webserver with SESAM connection

The APACHE Webserver (runnable on BS2000/OSD as well as on UNIX, Linux and Windows systems) has its own connection to SESAM/SQL-Server. SESAM/SQL databases can be queried and modified via the scripting language PHP (Hypertext Preprocessor). The PHP code is executed exclusively on the server, with only HTML code being transferred to the client. This means that the application logic remains hidden from the Web user, which ensures that increasedsecurity demands can be met in full. APACHE also supports Java servlets, which access the SESAM/SQL databases via the JDBC interface.

Taking existing SESAM applications onto the internet/intranet: WebTransactions

WebTransactions provides easy-to-use functions to web-enable existing SESAM/UTM applications. This applies particularly to applications developed using the DRIVE 4th-generation programming language.

WebTransactions is a very successful product, already well established in the marketplace, offering a broad range of potential applications involving integration of business-oriented applications and associated data with the World Wide Web.

(11)

4 The integrated OLTP system: SESAM/SQL-Server and openUTM

An important application area for database systems is online transaction processing (OLTP). In an OLTP application, a very large number of users access the same programs and data. This is normally done under the control of a transaction monitor (TP monitor). Typical OLTP systems are booking systems, financial accounting systems and inventory management systems. In combination with the openUTM transaction monitor, SESAM/SQL-Server makes a high-performance OLTP system. The performance capabilities of openUTM and SESAM/SQL-Server are particularly vividly demonstrated in large-scale installations to which several thousand users are connected and in which several hundred transactions per second are performed.

In OLTP applications, openUTM performs the following important functions:

„ openUTM ensures that response times remain short even with a large number of users on the system. Under its control, numerous user requests are processed by a small number of system tasks, thus minimizing the administration overhead of the system.

„ openUTM assumes responsibility for the monitoring, control and execution of user requests and controls communication with the database system. SESAM/SQL-Server and openUTM have the same view of transactions and conversations.

„ In the event of the system being interrupted, openUTM activates an automatic restart of the application and the screen form, which is synchronized with the DB system.

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5 Overview of the new features offered by SESAM/SQL-Server V6.0

Compared to the previous version, V5.0, SESAM/SQL-Server V6.0 offers the following important enhancements:

„ SQL Enhancements

• JDBC V4.0 support

The latest standard, JDBC V4.0 (included in Java SE 6), is offered on the JDBC interface with various “ease-of-development” functions.

• Native XML with JDBC

The new JDBC V4.0 interface WebRowSet enables the transfer of data from the database to standardized XML documents as well as writing back to the database the values changed externally in the XML document. • Reading external files

A new SQL feature permits the use of external files in CSV format as SQL tables in FROM clauses. • Data encryption

The data values of selected columns can be stored encrypted with the standard algorithm AES (Advanced Encryption Standard).

„ Utility functions

• REORG ONLINE

With the new utility REORG ONLINE, the reorganization of a single table of a space can be performed parallel to the database operation.

• RECOVER to time stamp

The command RECOVER CATALOG TO ANY TIMESTAMP x sets the database to the status of any desired timestamp x. • UNLOAD ONLINE

With the extension of the UNLOAD command the data to be unloaded can be selected as required by specifying a WHERE clause and sorted via an ORDER BY clause. Furthermore, data can not only be unloaded from a basic table as before, but also from a view.

„ Special BS2000 functions

• Extension of data spaces to other storage areas

After implementation for the secondary data buffer (in V4.0), the 64-bit addressing has been extended to cover the primary data buffer. Both can then be created to a maximum of 48 GB altogether.

• Large I/O transfer sizes

Large I/O transfer sizes (64 - 160 KB depending on the disk type) are now used as much as possible in the DBH task and in the service task.

• SESADM outputs in SDF list variables

The SESADM administration program outputs can be saved in SDF list variables and thus be automatically processed further.

• openSM2 connection

Data of the SESMON performance monitor can be transferred to the BS2000/OSD software monitor openSM2 (from V8.0) and shown here in a separate report group or graphically edited with the component INSPECTOR.

6 Summary

„ SESAM®/SQL-Server, the BS2000/OSD relational database system, supports many hundreds of thousands of end users worldwide and is one of the leading database systems for mainframes.

„ For years, SESAM/SQL-Server has provided daily proof of its exceptional business-critical computing capability.

„ Outstanding scalability and maximum availability make a reliable basis for business-critical web solutions.

„ Highly sophisticated self-management features reduce operating costs.

„ A convenient web connection, e.g. a dedicated SESAM/SQL interface in the Apache webserver and the ability to store XML documents in SESAM/SQL databases, ensures problem-free access to the web.

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All rights reserved, including intellectual property rights. Technical data subject to modifications and delivery subject to availability. Any liability that the data and illustrations are complete, actual or correct is excluded.

Designations may be trademarks and/or copyrights of the respective manufacturer, the use of which by third parties for their own purposes may infringe the rights of such owner.

Copyright © Fujitsu Technology Solutions GmbH 2009

Published by department: Frank Schützhold Phone: ++49 89 3222 2627 frank.schuetzhold@ts.fujitsu.com ts.fujitsu.com Partner login partners.ts.fujitsu.com

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