Before Query Business Rule Vs ACLSummary Before Query Business Rule Vs. ACL Even though both ACL and Business Rule are both server-side. The following are the key difference between them: Access Controls, limit data visibility to those who need it. but below are the cons of it: The dreaded 'Number of rows removed from this list by Security constraints' message. Many organizations don't want their users to know they are being denied access, but this message makes it all too apparent.In large lists of data, the 'allowed' records do not bubble to the top - they can be hidden pages down in the list where they are difficult for users to find.In a script-based ACL, the script must run for each row returned - In some cases, this can cause significant performance degradation. Before Query Business Rules are just what they sound like - Business Rules that run before the query on a table occurs. They offer an opportunity to add query terms that will limit the data returned, and can therefore act as security measures. There are many advantages to using these where possible: Because the list of data returned is pre-filtered, no more 'Number of rows removed from this list by Security constraints' message, and all data is returned in a clean list that is seemingly 'un-filtered' to the end-user.If scripting or an additional query is necessary to determine how the data must be filtered, it is far more efficient to do that once in a Before Query Business Rule than to do it hundreds or thousands of times through iterative runs of an Access Control script on each row of the table. The following are Key Advantages of Before Query Business Rule over ACL: 1. Performance: Before query is better because the conditions/filters run the initial Database query level. 2. User Experience: Before Query is better because you don't get the security message in the bottom of the ListView saying 'some records removed due to security" which might confuse the user. Though ACL has its own advantages (for example - field level restriction..etc)Related LinksNote: If any record has ACL which allows access to the record and the Before Query Business Rule which restrict the access of the record. The user will not be able to access the record.