SQL/MX 2.x Query Guide (G06.24+, H06.03+)

Operators and Operator Groups
HP NonStop SQL/MX Query Guide—523728-003
7-30
MERGE_UNION Operator
The MERGE_SEMI_JOIN operator has two child nodes. The description field for this
operator contains:
The example of the MERGE_SEMI_JOIN operator is based on:
INSERT INTO $sql06.sch184.d2pwl24
(SELECT* FROM $big18a.sqldpops.b2pwl24
WHERE sdec9_uniq IN (SELECT DISTINCT(sdec2_500)
FROM $big18a.sqldpops.b2pwl10));
4 8 9 merge_semi_join
merge_join_predicate:
(indexcol(\TESTSYS.$BIG18A.SQLDPOPS.B2PWL24.SDEC9_UNIQ) =
cast(indexcol(\TESTSYS.$BIG18A.SQLDPOPS.B2PWL10.SDEC2_500)))
join_type: inner semi
join_method: merge
parallel_join_type: 1
MERGE_UNION Operator
MERGE_UNION Group
The MERGE_UNION operator describes that part of an execution plan that merges
rows from two child nodes. The operator for a MERGE_UNION operator is always
MERGE_UNION.
The MERGE_UNION operator has two child nodes. The description field for this
operator contains:
Token Followed by... Data Type
merge_join_predicate Expression of the join
predicates
expr(text)
join_type Inner, left, natural,
inner semi, or inner
anti-semi-join
text
join_method Name of join method text
parallel_join_type Type1 or Type2,
depending on parallel
join algorithm
text
Token Followed by ... Data Type
union_type Merge text
sort_order Sort order of the result of the
union
text
merge_expr Expression used to
determine which child
operator to read from next:
read from left if true, or read
from right if false
expr(text)