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
7-51
NEXTVALUEFOR Operator
fragment_id ............ 0
parent_frag ............ (none)
fragment_type .......... master
join_type .............. inner semi
join_method .............. nested
NEXTVALUEFOR Operator
The NEXTVALUEFOR operator obtains the next values from the
SEQUENCEGENERATOR operator, and then assigns the value to the IDENTITY
column in the row.
The description field for the operator contains the following:
The following is an example of the NEXTVALUEFOR operator:
CREATE SEQUENCE cat.sch.s1;
PREPARE SeqQuery1 FROM SELECT s1.NEXTVAL FROM (VALUES (1)) x;
DESCRIPTION
max_card_est ........... 1
fragment_id ............ 0
parent_frag ............ (none)
fragment_type .......... master
generated_next_value ... \:_sys_hostNextValue
expected_outputs_from_s CAT.SCH.S1.CURRENT_VALUE,
\:_sys_hostVarNextNValues
Token Followed by ... Data Type
max_card_est Cardinality estimate for the operator. integer
fragment_id A sequential number assigned to the fragment.
0 is the master executor and 1 is reserved for
the EXPLAIN plan. Numbers 2 to n will be ESP
or DAM fragments.
integer
parent_frag The fragment_id for the parent of the current
fragment. The value is (none) for the master
executor.
integer
fragment_type Master, ESP. text
generated_next_value The expression calculates the next value for the
IDENTITY column. The expression calculates
the next value using
current_value_from_sg,
sg_cache_size_hv, and sg_increment_hv
sent by SEQUENCEGENERATOR operator.
expr(text)
expected_outputs_from
_s
The expression specifies the outputs expected
from the child SEQUENCEGENERATOR
operator.
expr(text)
TP663851.fm Page 51 Wednesday, January 30, 2013 5:37 PM