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Figure 3-7.
Sample query profile
The first point to note is that view expansion has occurred. The example query
references the view
v_supplier_part
, which the query optimizer has expanded into its
constituent tables and join criteria.
As you can see in Figure 3-7, there is a lot happening. Let’s break the profile down
into its constituent parts. Here’s an explanation of each step:
1.
The warehouse used to execute the sample query is displayed. I
prefer to put the warehouse size into my naming convention to
provide context, but as I will discuss later, there is no guarantee
the name correlates to the actual warehouse size.
ChapTer 3
The Query profiler