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
7-88
UNPACK Operator
elements from the array to use in the query. For more information about rowsets and
arrays, see the SQL/MX Programming Manual for C and COBOL.
The UNPACK operator has one child. The description field for this operator contains
the following:
Create a module file. For details on creating module file, see the SQL/MX
Programming Manual for C and COBOL.
Now execute the following command:
explain <name of a statement in module file> from <name of
module file>
The following is an example of the UNPACK operator:
DESCRIPTION
fragment_id ............ 0
parent_frag ............ (none)
fragment_type .......... master
unpack_expression ...... (:a RowsetArrayScan
\:_sys_rowset_index1),
(:b
RowsetArrayScan\:_sys_rowset_index1),
(:c
RowsetArrayScan\:_sys_rowset_index1)
packing_factor ......... 200
index_value .............. \:_sys_rowset_index1
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 of the current
fragment. The value is (none) for the master
executor.
integer
fragment_type Master, ESP, or DP2 text
unpack_expression Expression used to extract values from a
packed row
expr(text)
index_value System-generated index used when accessing
a packed row
expr(text)
packing_factor Used to extract the packing factor from the
packed row. The packing factor is the number
of logical rows in the packed row.
integer
TP663851.fm Page 88 Wednesday, January 30, 2013 5:37 PM