SQL/MX 2.x Installation and Management Guide (G06.24+, H06.03+)

Reviewing and Setting System Defaults
HP NonStop SQL/MX Installation and Management Guide—523723-004
6-3
New System Defaults for Release 2.0
New System Defaults for Release 2.0
Table 6-1 lists the system defaults that are new for Release 2.0. For a complete list of
system defaults and their default values, see the SQL/MX Reference Manual.
Table 6-1. New System Defaults for Release 2.0 (page 1 of 3)
Default Description
CACHE_HISTOGRAMS_
REFRESH_INTERVAL
Controls interval at which histograms are refreshed.
DP2_CACHE_4096_BLOCKS Specifies the number of 4 KB blocks allocated for the
disk cache. The specified value is used by the compiler
to determine the cost of a table/index scan operator.
DYNAMIC_HISTOGRAM_
COMPRESSION
Reduces the number of histogram intervals for
histograms of base table columns when those
histograms are read from disk.
FLOATTYPE Controls whether the output of FLOAT data types is
treated as Tandem FLOAT or IEEE FLOAT.
GEN_MAX_NUM_PART_DISK_
ENTRIES
Controls the size of a partition list prepared by the
compiler and used by the executor.
GEN_MAX_NUM_PART_NODE_
ENTRIES
Controls the size of a partition list prepared by the
compiler and used by the executor.
HIST_NO_STATS_REFRESH_
INTERVAL
Controls the interval at which default statistics are
refreshed.
HIST_SECURITY_WARNINGS Controls whether MXCMP displays a warning if the user
does not have access permissions to statistics tables
and the user table’s estimated rowcount is greater than
the HIST_ROWCOUNT_REQUIRING_STATUS value.
INDEX_ELIMINATION_LEVEL Indicates the degree of heuristic elimination of indexes
consideration by the optimizer.
INTERACTIVE_ACCESS Influences the optimizer’s choices for access paths of
the tables in a query. INTERACTIVE_ACCESS causes
the optimizer to give preference to query plans that use
key access on indexes. When set to ON, the compiler
selects the most appropriate index-based access plan.
When set to OFF, the compiler follows normal behavior
and does not emphasize index-based access plans.
The default is OFF.
MAX_ROWS_LOCKED_FOR_
STABLE_ACCESS
Maximum number of rows that are locked in STABLE
ACCESS mode
MSCF_ET_REMOTE_MSG_
TRANSFER
Factors in the cost of transferring messages to and from
a remote node.
MXCMP_PLACES_LOCAL_
MODULES
Controls the location where compiled modules are
placed.