Improve The Execution Time
i am new to db2 want to ask questions about the performance of my sql commands for a view based another 3 views
the sql commnads are as following:
create view b_central_subgroup as
select communicator as central_member, project_id as project_id
from b_normalized_communicator
intersect
select initiator as central_member, project_id as project_id
from b_normalized_initiator
intersect
select monospeaker as central_member, project_id as project_id
from b_normalized_monospeaker
it takes 4.4 seconds to execute this sql.
it likes that the time is the summ of the other three views.
Can the execution time be reduced through some other methods?
If it is possible , then how ?
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