To maintain the integrity and operability of enterprise database systems, queries intended for a particular database engine are intercepted, preferably by a separate processing system, prior to being acted upon by the database engine. The query is evaluated to determine its projected impact on available database system resources. The variables evaluated include user rights, administrator-imposed limits to searches, the amount of presently-available system resources, the cost of query and the like. If the query's potential impact does not surpass a predetermined threshold, it is submitted to the search engine. If the query is too resource-intensive or costly, the query may be (i) optimized by a query-optimization system, (ii) stored until more system resources are available, or (iii) rejected.