SYSTEM AND METHOD FOR DYNAMIC MEMORY ALLOCATION FOR QUERY EXECUTION

Methods, systems, apparatuses, and computer-readable storage mediums described herein are directed to dynamic memory allocation for query execution. A memory grant engine is configured to analyze query runtime execution statistics of instances of a query to detect whether memory allocation operations performed for the query in accordance with a first memory allocation policy (e.g., a last used grant-based policy) changes across executions of that query. Upon detecting such a pattern, the engine dynamically switches to utilizing a second memory allocation policy, such as a percentile-grant based policy. In accordance with such a policy, the engine determines an amount of memory space to be allocated for subsequent instances of the query based on an analysis of query runtime execution statistics of previous instances of the query. The determined amount of memory space is configured to satisfy a predetermined percentile value of the previous instances of the query.