What is the difference between the Memory Metrics in Query_Requests VS Resource_Acquisitions
We are performing analysis of memory usage of queries and are curious about the differences between the values reported in the 2 v_monitor columns below. The Definitions of these columns in the SQL Ref manual are nearly the same, yet query_requests.memory_acquired_mb is often null, or does not match value in resource_acquisitions. Is a more detailed definition of these 2 columns available?
v_monitor.resource_acquisitions column memory_inuse_kb
Amount of memory in kilobytes acquired by this request
v_monitor.query_requests column MEMORY_ACQUIRED_MB
Memory acquired by this query request in megabytes
Thanks for any Information you can provide