1 Data Dictionary.pdf

Data Dictionary Day 2 We will learn about… ? What is Data Dictionary ? Data Dictionary Objects ? System Fields ? Creating custom table ? Internal Tables ? Foreign Keys Cardinality ? Structures ? Views What is Data Dictionary ? is a system independent interface to the database ? is a virtual database ( data about data) ? provides data for data manipulation and data processing ? Also called as DDIC and ABAP Dictionary Data Dictionary Objects ? Data Element ? Domain ? Tables ? Structures ? Views SE16 Elementary Data Types Type Explanation C Text (Character) N Numeric text D Date (DDMMYYYY) T Time (HHMMSS) X Hexadecimal I Integer P Packed Number F Floating point number Domain ? A Domain describes the technical structure of a field that is its size and its data types. ? Domains are attached to Data Elements ? Fields which refer to the same domain (with the assigned data elements), are also changed when the domain is changed. This ensures that the fields are consistent ? Defines a value range which describes the valid data values for all the fields which refer to this domain Domain MATNR CLNT Table MARA Data Element Creating a Domain Enter a description (short text) Enter data type and length Creating a domain (contd.) Enter fixed value and description. Value table may be entered Data Element ? A data element gives the description of the field of the Table ? Examples of predefined data elements in SAP – LIFNR – KUNNR – MATNR – CLNT Creating a Data Element Enter a description (short text) Enter domain name Creating a Data Element Maintain field labels and column headers. Difference between Domain Data Element Domain Data Element Defines Technical Attributes such as data type, length, allowed values, etc. Defines semantic attributes such as display length, short text, long text, etc A domain can be part of several data elements A Data Element can point to only one domain Used to define data elements, restrict values (using value range, value table, etc)