SQL/MP Installation and Management Guide

Reorganizing Tables and Maintaining Data
HP NonStop SQL/MP Installation and Management Guide—523353-004
8-7
Adding Empty Partitions
Adding Empty Partitions
If a table is filling its primary partition or its last secondary partition, you can add an
empty partition after the last existing partition to allow for growth. For relative or entry-
sequenced tables, the partition is always added to the end of the table. This type of
extension spreads the access to the table over additional volumes or nodes. For a
table of any organization, an empty partition can be added at any time. If any partition
of a key-sequenced table or index is nearly full, split the partition by using an ALTER
TABLE or ALTER INDEX statement, as described in Altering Database Objects on
page 7-13.
Loading, Copying, Appending, and Purging
Data
SQL/MP provides four utilities to move data into or out of tables and Enscribe files
offline: the SQLCI CONVERT, LOAD, APPEND, and COPY utilities. For LOAD,
APPEND, or COPY, the source file can reside on either disk or tape.
The CONVERT utility uses the LOAD utility to move the data from Enscribe files to
SQL tables. If you are converting Enscribe data files into SQL tables, use the
CONVERT utility directly.
The LOAD and COPY utilities have very similar options and perform similar tasks. The
basic differences follow:
•
LOAD enters data into an empty target table. The COPY utility appends or inserts
rows into an existing table without purging existing data.
•
LOAD provides options for processing key-sequenced files. You can specify, for
instance, that the rows are in sorted order. You can specify a maximum number of
rows to be loaded. You can define the DSLACK, ISLACK, and SLACK percentages
allowed. LOAD reorders unsorted input data and optionally uses a user-specified
scratch file location for the SORTPROG processes.
•
The LOAD utility is faster than COPY. LOAD sorts rows and then writes them in
blocks to the target table. COPY does multiple inserts, one row at a time.
•
LOAD enters data into any indexes already created on the table, overwriting any
existing data. COPY automatically inserts rows into indexes that already exist.
•
LOAD provides an option to load individual partitions of a table.
•
You can use COPY to copy data within a user-defined TMF transaction on an
audited table. You cannot use LOAD to load an entire audited table without
resetting the AUDIT attribute, but you can use LOAD to load data into a single
partition of an audited table.
•
You can use COPY to copy data from Enscribe unstructured files; LOAD does not
operate on unstructured files.