SAP ABAP Data Element DB2WP4SJRT (DB2 for OS/390: Star Join controls)
Hierarchy
SAP_BASIS (Software Component) SAP Basis Component
   BC-DB-DB2 (Application Component) DB2 for z/OS
     STU3 (Package) Development Class for Database Monitor
Basic Data
Data Element DB2WP4SJRT
Short Description DB2 for OS/390: Star Join controls  
Data Type
Category of Dictionary Type     Direct Type Entry
Type of Object Referenced     No Information
Domain / Name of Reference Type      
Data Type CHAR   Character String 
Length 10    
Decimal Places 0    
Output Length 10    
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 Star Join 
Medium 20 Star Join controls 
Long 30 Star Join controls 
Heading 30 Star Join controls 
Documentation

Definition

The value controls if and when a star join will be used in the access path selection process. Possible values are:

  • 0 : enable star join under current conditions (fact table 25x larger than any dimension table)
  • -1 : disable star join (the default)
  • 1 : enable star join, the fact table will be the largest table in the star join query, i.e. no fact/dimention ratio checking.
  • >1 : enable star join if the fact-table-to-dimension-table ratio is equal or larger than the given value.

ZPARM name is STARJOIN in DSN6SPRM.

History
Last changed by/on SAP  20110908 
SAP Release Created in 710