SAP Knowledge Base Article - Preview

2749378 - Query using "between" clause - choosing bad plan when data set increases - SAP ASE

Symptom

A join using the "between" clause where the lower and upper values are different columns, for example:

AB1.col1 between TAB2.colX and TAB2.colY

  • When working with a small set of data - the query runs quickly. 
  • The inefficient plan is selecting an index scan (See KBA 1988269 - How to collect diagnostic information for a query performance problem) 

|   |   |   |   |   |   |  Index : IDX_5
|   |   |   |   |   |   |  Forward Scan.
|   |   |   |   |   |   |  Positioning at index start.

  • Efficient plan is selecting an 

    |   |   |   |   |   |  Index : IDX_5
    |   |   |   |   |   |   |  Forward Scan.
    |   |   |   |   |   |   |  Positioning by key.
    |   |   |   |   |   |   |  Keys are: ...


Read more...

Environment

  • SAP Adaptive Server Enterprise (ASE) 15.03
  • SAP Adaptive Server Enterprise (ASE) 15.7
  • SAP Adaptive Server Enterprise (ASE) 16.0

Product

SAP Adaptive Server Enterprise 16.0

Keywords

inbetween sp_modifystats performance unefficient efficent unefficent bug , KBA , BC-SYB-ASE , Sybase ASE Database Platform (non Business Suite) , Bug Filed

About this page

This is a preview of a SAP Knowledge Base Article. Click more to access the full version on SAP ONE Support launchpad (Login required).

Search for additional results

Visit SAP Support Portal's SAP Notes and KBA Search.