NonStop SQL/MP Reference Manual

NonStop SQL/MP Reference Manual—142115
A-20
Considerations—ALTER INDEX
name specifies the partition being moved. You can specify a simple move with
or without the WITH SHARED ACCESS option.
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A merge operation moves the partition into another existing partition, deleting
the original partition:
MOVE TO dest-part WITH SHARED ACCESS
name specifies the actual partition being moved. The WITH SHARED
ACCESS option is required.
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A one-way split moves the first or last part of a partition to a new partition,
leaving the remaining part in the existing partition:
MOVE FROM KEY val TO dest-part [WITH SHARED ACCESS]
MOVE UP TO KEY val TO dest-part WITH SHARED ACCESS
In a one-way split, name specifies a partition of the index. The partition that is
split is the one whose data range would include the key val, even if the index
partition does not actually contain a row with that key.
For a one-way split operation, 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
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 must be
unique for each partition of the same object.
The first part can be moved only if you include the WITH SHARED ACCESS
option.
A one-way split without the WITH SHARED ACCESS option requires
additional space on the disk that contains the partition being split while the split
is in progress. The amount of additional space required can be as much as the
size (EOF) of the original partition. If you are splitting a partition because the
disk is full, use the WITH SHARED ACCESS option or use a two-way split.
After a successful one-way split operation, run FUP RELOAD to reclaim
unused space on disk. For more information, see the File Utility Program (FUP)
Reference Manual.
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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