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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FILE_SCAN Operator
The following is an example of the FILE_SCAN operator:
PREPARE TestQuery2 FROM
SELECT s_acctbal, s_name, n_name, p_partkey, p_mfgr, s_address,
s_phone, s_comment
FROM part,supplier,partsupp, nation, region
WHERE p_partkey = ps_partkey
AND s_suppkey = ps_suppkey
olt_opt_lean Indicates for short, simple operations whether a
further optimization that reduces the physical
size of the plan is used. Its value is used or not
used.
text
scan_type FILE_SCAN followed by table name. text
scan_direction Direction in which table is scanned: forward or
reverse
text
lock_mode The lock mode specified: shared, exclusive, not
specified (defaulted to lock cursor), or unknown.
text
access_mode The access specified: read uncommitted, skip
conflict, read committed, stable, serializable,
mx serializable, not specified (defaulted to read
committed), or unknown.
text
executor_predicate Any predicate expression that is not a key
predicate evaluated by the executor in DAM.
expr(text)
columns_retrieved Estimate of the number of columns to be
returned.
integer
fast_scan Indicates whether an optimization for a simple
scan operation is used. The value used is
returned if this optimization is used.
text
fast_replydata_move Indicates whether an optimization for returning
data from DAM is used. The value used is
returned if this optimization is used.
text
key_columns Columns used as the primary key. expr(text)
mdam_disjunct Disjunct key predicates used by MDAM. expr(text)
begin_key Expression of the begin key predicate. expr(text)
end_key Expression of the end key predicate. expr(text)
key_type Simple or MDAM. text
part_key_predicate Predicate expression specified on partitioning
key. Displayed only if partitioning key differs
from clustering key.
expr(text)
self_referencing_update Indicates the method used to prevent the
halloween problem. Possible values are
dp2_locks, forced_sort, and
none_required.
text
Token Followed by ... Data Type
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