SQL/MP Installation and Management Guide

Reorganizing Tables and Maintaining Data
HP NonStop SQL/MP Installation and Management Guide—523353-004
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Loading Individual Partitions
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If the LOAD utility fails during the LOAD operation, the target table or file is left in
an invalid state and is unusable. You can restart the LOAD operation to overwrite
the existing data using the same source file.
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If you are loading data from an Enscribe file into an SQL table, from an SQL table
into an Enscribe file, or from an SQL table into another SQL table, the data types of
the source and target fields or columns must be compatible. The rules for valid field
or column compatibility are the same as those described for the CONVERT utility
in the SQL/MP Reference Manual.
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You must create all target files or tables before issuing the LOAD command. LOAD
does not create the files or tables.
Loading Individual Partitions
The LOAD utility allows partitions of tables to be loaded separately. You must perform
these operations carefully to ensure that all partitions are loaded with logically
consistent data.
You can use the DataLoader/MP product to load data into multiple partitions of a fact
table or history table. Although you can use DataLoader/MP to load data into any
SQL/MP table, it is primarily useful for loading and maintaining large tables such as
those used in a data warehouse. With DataLoader/MP, you can initially populate a data
warehouse with data derived from an operational database; you can also perform
periodic load operations that update an existing data warehouse. DataLoader/MP can
use the LOAD utility to perform load operations. Therefore, users of DataLoader/MP, in
addition to users of the LOAD utility, should read the following description of loading
partitions. For more information about the DataLoader/MP product, see the
DataLoader/MP Reference Manual.
Loading a Single Partition
This example loads a secondary partition of the ORDERS table that resides on
$VOL1.MKT when the primary partition resides on $VOL4.MKT:
>> LOAD $OLD.SALES.ORDERS, $VOL1.MKT.ORDERS, PARTONLY;
When you load a single partition of an audited table, you need not reset the AUDIT
attribute before the load operation. This action is only required when loading an entire
audited table. Be sure to do an online dump of the partition when the load is finished if
you want to preserve TMF recovery capability.
Loading Multiple Partitions in Parallel
The PARTONLY option lets you load partitioned base tables in parallel. This strategy
can improve load performance if table partitions are distributed across disks,
processors, and I/O channels. These steps describe possible strategies for loading
partitions in parallel: