SQL/MX 2.x Query Guide (H06.04+, J06.03+)

SQL/MX Operators
HP NonStop SQL/MX Query Guide—540437-005
7-18
FILE_SCAN_UNIQUE Operator
The FILE_SCAN_UNIQUE operator has no child nodes. The description field for this
operator contains:
Token Followed by ... Data Type
fragment_id A sequential number assigned to the fragment.
0 is always 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 fragment of the
current fragment. The value is (none) for the
master executor.
Integer
fragment_type Master, ESP, or DP2. text
olt_optimization Indicates whether an optimization for short,
simple operations is used. Value is used if this
optimization is used. Its value is used or not
used.
text
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
key_columns Columns used as the primary key. expr(text)
key Expression of the key predicate. expr(text)
scan_type Unique access of table, followed by table
name.
text
key_type Simple or MDAM. text
lock_mode The lock specified: read uncommitted, skip
conflict, read committed, stable, serializable,
mx serializable, not specified (defaulted to read
committed), 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
columns_retrieved Estimate of the number of columns to be
returned.
integer
executor_predicates Any predicate that is not a key predicate
evaluated by the executor in DAM.
expr(text)