Neoview Query Guide (R2.2)
The LEFT_NESTED_JOIN has two child operators. The description field for this operator contains:
Data TypeToken DescriptionToken
integerA sequential number assigned to the fragment. 0 is always master executor
and 1 is reserved for the Explain plan. Numbers 2 to n will be ESP or DAM
fragments.
fragment_id
integerThe fragment_id for the parent fragment of the current fragment. Value
is (none) for master executor.
parent_frag
textmaster, ESP, or DAMfragment_type
textLeft joinjoin_type
textName of join method: nested or in-order nested joinjoin_method
text1 for Type1 for 2 or Type2, depending on parallel join algorithmparallel_join_type
expr(text)Expression of the ON clause that has not been pushed down to the inner
scan, typically empty
join_predicate
expr(text)Expression of the WHERE clause that has not been pushed down to the
inner scan, typically empty
selection_predicates
TUPLE_FLOW Operator
The TUPLE_FLOW operator describes a portion of an execution plan that typically involves an
insert-select or a rowset insert, implemented as a type 1, matching partitions nested join. All
rows from the outer table are selected and inserted into the inner table. This operator enables
data to flow from one child to the other. The join_predicate and selection_predicates expressions
are empty. As with the nested join, for the inner child tree you need to review the PROBES field
of the COST_DETAILS panel in VQP to find the estimated cardinality for the operation.
This operator facilitates fast and efficient parallel, sequential inserts and is frequently preceded
by a sort operation.
The TUPLE_FLOW operator has two child operators. The description field for this operator
contains:
Data TypeToken DescriptionToken
integerA sequential number assigned to the fragment. 0 is always master executor
and 1 is reserved for the Explain plan. Numbers 2 to n will be ESP or DAM
fragments.
fragment_id
integerThe fragment_id for the parent fragment of the current fragment. Value
is (none) for master executor.
parent_frag
textmaster, ESP, or DAMfragment_type
textInner joinjoin_type
textName of join method: nested or in-order nested joinjoin_method
text1 for Type1 or 2 for Type2, depending on parallel join algorithmparallel_join_type
expr(text)Expression of the ON clause that has not been pushed down to the inner
scan, typically empty
join_predicate
expr(text)Expression of the WHERE clause that has not been pushed down to the
inner scan, typically empty
selection_predicates
Understanding Joins 39