Methods and apparatuses are described for system for identifying and mitigating high-risk database queries through ranked variance analysis. A server identifies database queries executed against databases in a production computing environment within a predetermined time period, each database query associated with execution plans and each execution plan having corresponding plan data elements. For each database query: the server generates execution variance data for the execution plans for a database query based upon the corresponding plan data elements, comprising: determining an execution time variance between the execution plans; and determining a buffer gets variance between the execution plans. The server ranks the database queries according to (i) the execution time variance, and (ii) the buffer gets variance. The server computing device identifies high-risk database queries based upon the rank, and adjusts execution settings for each of the identified high-risk database queries to mitigate performance degradation in the production computing environment.