SQL/MP Reference Manual

HP NonStop SQL/MP Reference Manual—523352-013
A-21
Considerations—ALTER INDEX
Reference Manual. You can also run DCOM on the disk to reclaim unused
space. For more information on DCOM, see the Guardian Disk and Tape
Utilities Reference Manual.
If you are splitting a partition because the file is full (error 45), increase
MAXEXTENTS for that file, if possible. Otherwise, perform a two-way split.
If you are splitting a partition because you received SQL error -1637 (“An
unexpected error occurred while purging data from filename”), verify that the
error was received against the source partition. If the error was on the
destination partition, specify smaller extent sizes based on the largest free
segment on that disc, or obtain a DSAP report and specify another volume
based on the largest free space available on another disk.

A two-way split moves the first part of a partition to one new partition and the
last part of a partition to another new partition, deleting the original partition:
MOVE UP TO KEY val TO dest-part
FROM KEY val TO dest-part
In a two-way split, name specifies the partition for the operation.
Both occurrences of val must be identical, but each occurrence of
dest-part must specify a different partition. That is, the subvolume name
and simple file name for the new partition (whether specified explicitly or by
default) must be identical to the subvolume name and simple file name for
every other partition of the same object. ALTER INDEX uses those names if
you specify only a node name and a volume name or specify only a volume
name (which causes the node to default to the local node). The combination of
node name and volume name, specified as dest-part, must be unique for
each partition of the same object.
The two-way split does not support the WITH SHARED ACCESS option.

A one-way move operation moves the first or the last part of a partition to its
logically adjacent partition, leaving the other part in the existing partition. This
operation essentially moves the boundary of the partition; for example:
MOVE UP TO KEY val TO dest-part WITH SHARED ACCESS
MOVE FROM KEY val TO dest-part WITH SHARED ACCESS
A one-way move is similar to a one-way split, but moves data to an existing
partition instead of a new partition.
In a one-way move, name specifies a valid partition of the index. NonStop
SQL/MP determines the actual source partition during execution. The WITH
SHARED ACCESS option is required.
After a successful one-way move operation, run FUP RELOAD to reclaim
unused disk space. For more information about FUP RELOAD, see the File
Utility Program (FUP) Reference Manual.

Reconfiguring partitions of indexes