If QM searches the query plan in buffer and QB and fails to find then it passes the new query to
SQOEPL, then SQOEPL parsed the query in different ways then presented to a query processor that
select the best plan and load it in to the QB. Then the best plan is passed to the NQHO. After the
execution of best plan the WM assigns weight one to the query and query with its executed plan is saved
into QB and SQOEPL once again refreshes the buffer, it takes the buffers queries into QB and loads the
queries of highest weight from QB into buffer again.
x Query Bank
All executed queries and their best plans are stored in Query Bank in descending order according to
weight assigned by Weight Manager. When database application is closed all queries and their plans are
moved to Query Bank.
x Query Coordinator
For the creation of new execution plans query coordinator provides database statistics from data
dictionary and for the processing of query it provides data from database also. If the data is not available
in local database then Query Coordinator searches the index in different site simultaneously retrieve and
by finding out spatial nodes whose MBR enclose the appoint point.