SAP ABAP Data Element CARDLEFT (Cardinality of a relationship)
Hierarchy
SAP_BASIS (Software Component) SAP Basis Component
   BC-DWB-DIC-AC (Application Component) Activation Program, Conversion Program, DB Utility, MC, SPDD
     SDTB (Package) ABAP/4 Dictionary: Tables
Basic Data
Data Element CARDLEFT
Short Description Cardinality of a relationship  
Data Type
Category of Dictionary Type D   Domain
Type of Object Referenced     No Information
Domain / Name of Reference Type CARDLEFT    
Data Type CHAR   Character String 
Length 2    
Decimal Places 0    
Output Length 1    
Value Table      
Further Characteristics
Search Help: Name    
Search Help: Parameters    
Parameter ID   
Default Component name    
Change document    
No Input History    
Basic direction is set to LTR    
No BIDI Filtering    
Field Label
  Length  Field Label  
Short 10 Card 
Medium 18 Cardinality 
Long 20 Cardinality 
Heading Cd 
Documentation

Definition

The cardinality (n : m) describes the foreign key relationship with regard to the number of possible dependent records involved (records of the foreign key table) or referred records (records of the check table).

The left side of the cardinality has the following significance:

  • n = 1

    For each dependent record there is exactly one record of the check table.

  • n = C

    There can be records in the foreign key talbe which do not reference any record of the check table.

Note:
The definition of a generic foreign key means that the cardinalties (1 : m) and (C : m) actually become (CN : m). There can be several records of the check table for each dependent record. The value n = CN cannot however be specified explicitly in maintenance because a CN : m relationship is equal to a foreign key.

History
Last changed by/on SAP  19970321 
SAP Release Created in