Memory Usage

One of my friend's question:
"When I get a big result by a query (such as 1M of rows), the memory usage
of my system decreasing critically. What is the phenomenon that causes this
behaviour?"
Ok it is usual, because I can still observe the rows in the result pane
below. But, Although I close the pane, the mem.usage is still high.
I think it occurs because of the cached result in order to respond later
requests in a fast manner.
Can you please make a comment about the subject?
AND, I would like to learn if there is a way to release/flush this memory by
the Query Analyzer.That happens by design. It's not a flaw or memory leakage.
It is really not the Query Analyser that is "eating the memory", but
instead SQL Server that is behaving according to the Memory settings
established on Enterprise Manager.
Open EM, right click the server registration you wish to check and
click Properties. Move to the memory tab. It is recommended that the
server is configured to dynamically allocate memory.
SQL Server will use as much memory as it can. As other process may
start requesting memory, it will release it. Untill then, it will keep
his own memory usage. With queries being run on the Query Analyser, the
memory usage will keep increasing just short of having to start paging.
I know of no way to programatically release this memory. However, I
don't think this is an issue, since any other process that needs memory
will have it released by SQL Server.