ABAP Dictionary Tables in Relational Databases
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Objectives
• The participants will be able to: – Describe the different types of tables in the SAP
ABAP Dictionary.– Explain the technical settings for optimizing the
storage and maintenance requirements.– Describe performance benefits through indexing.
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SAP Table Types
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Transparent Table (TRANSP)
Structure (INTTAB)
Pool Table Cluster Table
View
Transparent Tables
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Master Data
SAP stores both master data and transaction data exclusively in transparent tables.
Transactional Data
Table Types TRANSP in the Database
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DB
PROFILE
Transparent (TRANSP) tables have a 1:1 correlation between the ABAP Dictionary and the physical database.
Mapping a Table of Type INTTAB
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DB xx
PROFILE
INTTAB tables are field strings (structures) which do not hold data.
They are not mapped to the database and have no underlying database tables.
Pool and Cluster Tables: Overview
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Pool Table Cluster TableCluster Table
Pooled tables can be used to store control data (e.g. screen sequences, program parameters or temporary data).
Cluster tables contain continuous text (e.g. documentation).
Technical Settings
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Master, Transaction Organization &
Customizing, UserData class
Number of data records in DB storage
Single records buff, generic area buffered, fully buffered
On or off
Size category
Buffering
Log data changes
Data Class
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User dataMaster data
Organization and Customizing dataTransaction data
DB
Size Categories
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A table’s size category identifies the amount of disk space on the database that is allocated to the table.
Buffering Type
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None
Single Record Generic
Full
KF1 KF2 KF3 F4 F5 F6 KF1 KF2 KF3 F4 F5 F6
KF1 KF2 KF3 F4 F5 F6
Logging
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On the technical settings screen you can specify “Log data changes” to automatically generate a log file of details on the structure of a table, a list of the data changes made during a certain period, and statistics.
Maintaining Technical Settings
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Data Class
Size Category
Buffering Type
Logging
Demonstration•Observation of the technical settings of the SAP Table MARA and familiarization with the technical settings of a transparent table.
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Practice
•Observation of the technical settings of the SAP Table MARA and familiarization with the technical settings of a transparent table.
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Database Utility
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ABAP ABAP Dictionary
Dictionary
DB
The Database (DB) Utility is a tool used in SAP to serve as a interface between the database management software (i.e., ORACLE, INFORMIX, DB2, INGRES, etc.) and the ABAP Dictionary
Index
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To improve performance, SAP automatically creates a primary index (id 0) for transparent tables based on the primary key. You can also define your own secondary indexes for transparent tables.
Database Indexes
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Index Table
Last NameLast Name First NameFirst Name PointerPointer
Adams Anthony
IDID Last NameLast Name First NameFirst Name SalarySalary
Zelkova Zephyr
Employee Names Employees
Burrows
Jones
Furia
Peters
Treske
Gregory
Gerry
Fred
Tim
Jimmy
Beth
Carolin
The Telephone Book Analogy
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Think of an index like a telephone book
The Telephone Book Analogy (Contd.)
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The Index Range Scan
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Sometimes an index doesn’t point to a single record, so it has to go for the Index Range Scan
The Unique Index Scan
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If each index record matches exactly one record in the table, and if all the fields of the index are specified in the query, a unique index scan can be performed.
Evaluating the Various Types of Scans
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Unique Index ScanUnique Index Scan
Index Range ScanIndex Range Scan
Full Table ScanFull Table Scan
A unique index scan is generally faster than an index range scan, because it has less data to sort through and retrieve.
Summary• There are 5 different table types in the SAP ABAP Dictionary: Transparent tables,
Structures, Pool tables, Cluster tables & Views.• Technical settings allow you to optimize the storage requirements and table
access behavior of database tables.• Defining a data class has the effect of storing the table in a defined area of the
database when the table is created.• A table’s size category identifies the amount of disk space on the database that is
allocated to the table. • Buffering is only recommended for tables with data that typically does not change
or get updated.• To improve performance, SAP automatically creates a primary index (id 0) for
transparent tables based on the primary key. You can also define your own secondary indexes for transparent tables.
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Questions• What are the different table types ?• What is data class ?• What is size category ?• What is buffering ?
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