SQL/MX 3.2.1 Query Guide (H06.26+, J06.15+)

SQL/MX Operators
HP NonStop SQL/MX Release 3.2.1 Query Guide—663851-003
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ROOT Operator
ROOT Operator
Root Group
The ROOT operator is the root, or the top node, of an execution plan and describes the
SQL query. The operator for a ROOT is always ROOT.
The ROOT operator has one child. The description field for this operator contains the
following:
Token Followed by ... Data Type
statement Original SQL statement text
select_list Expression of the SELECT list columns expr(text)
input_variables Expression containing list of input variables
(params)
expr(text)
order_by Expression containing list of sort keys expr(text)
must_match When CONTROL QUERY SHAPE is used,
textual description of forced query tree ()
expr(text)
update_col The update column specification of an
updatable cursor declaration
expr(text)
olt_optimization Indicates whether an optimization for short,
simple operations is used. The value used is
returned if this optimization is used.
text
statement_index Statement index of this statement as reported
by the Measure product.
integer
upd_action_on_error Determines the type of statement atomicity
chosen for a query:
XN_ROLLBACK: Transaction is rolled back if
an error occurs.
RETURN: Query stops executing and error is
returned without need for statement rollback.
SAVEPOINT: DAM savepoints are used to roll
back the statement if an error occurs.
PARTIAL_UPD: [NonStop SQL/MP style]
Partial results are updated and an error is
returned.
text
self_referencing_update Indicates the method used to prevent the
halloween problem. Possible values are
dp2_locks, forced_sort, and
none_required.
text
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