NonStop SQL/MP Reference Manual

NonStop SQL/MP Reference Manual—142115
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Examples—=_SORT_DEFAULTS
volume. Using =_SORT_DEFAULTS can also prevent errors caused when DML
operations encounter a full disk.
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If the swap and scratch files you specify do not exist at the time of the FastSort
operation, FastSort creates them and uses MAXEXTENTS 160. If you create the
files yourself, you must choose an appropriate file size.
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If you specify swap or scratch files on a LOAD command or in the configuration
file for parallel execution of a CREATE INDEX or LOAD command, those file
specifications override any file specifications in =_SORT_DEFAULTS for that
LOAD operation.
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If ServerWare SMF is installed on your node, you can specify either a virtual or
physical volume for the SCRATCH parameter. However, only physical volumes are
valid values for the SCRATCHON and NOSCRATCHON parameters.
If you specify a virtual volume for SCRATCH, the sort process ignores any
overflow scratch volumes you specify in SCRATCHON and NOSCRATCHON.
Because FastSort does not automatically create and manage overflow scratch files
when you specify a virtual volume for SCRATCH, the virtual volume must have
space available for all scratch files for the sort operation.
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An error occurs if you add =_SORT_DEFAULTS without specifying CLASS SORT
either explicitly or through the working attribute set.
See the TACL Reference Manual or the FastSort Manual for more information about
=_SORT_DEFAULTS.
Examples—=_SORT_DEFAULTS
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The following SQLCI command specifies scratch and swap volumes for FastSort
operations:
>> ADD DEFINE =_SORT_DEFAULTS, CLASS SORT,
+> SCRATCH $DISKA, SWAP $DISKB;
The specified volumes will be used for SQL queries or utility operations that call
FastSort as long as the DEFINE remains in effect.
=_SQL_CAT_HEAP_LIMIT DEFINE
=_SQL_CAT_HEAP_LIMIT is a system DEFINE that specifies the heap space size for
the SQLCAT process. Some SQL DDL or utility statements require a large memory
heap in the SQLCAT process. The catalog manager currently allocates 4 MB of heap
space that can expand to 16 MB. You can use this DEFINE to allocate a larger heap.
ADD DEFINE =_SQL_CAT_HEAP_LIMIT, [CLASS MAP, ]
FILE Mheap-space-size