Rule Definition
Some addition automatically bypass buffer. Bypassing buffer means that SELECT will not go to buffered results but always directly to the database. This can impact the performance significantly.
Remediation
Check if the IS NULL addition is really necessary and use this addition carefully.
Reference
NetWeaver Performance Notes
http://help.sap.com/saphelp_nw70/helpdata/en/aa/4734a00f1c11d295380000e8353423/frameset.htm
Related Technologies
Technical Criterion
Efficiency - SQL and Data Handling Performance
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