8.1.3 Unloading a table

Organization of this subsection
(1) What is unloading a table?
(2) Migrating data into another table
(3) Modifying table partitioning conditions
(4) Using an unload data file as pdload's input data file or with a UAP
(5) Unloading a table with LOB columns or abstract data type columns provided by a plug-in (LOB attribute)
(6) Unloading a table using a UOC
(7) Using a utility special unit

(1) What is unloading a table?

Table reorganization involves saving the table data into a file and then storing the data from the file back into the table. This process for saving table data in a file is called unloading a table.

You can unload a table in units of tables or RDAREAs (applicable to row-partitioned tables).

Figure 8-6 shows an overview of unloading a table.

Figure 8-6 Overview of unloading a table

[Figure]

(2) Migrating data into another table

To migrate data into another table, first save the table data to an unload data file and then reload the data from the unload data file into the other table. Note that the target table must have the same attribute (FIX or non-FIX) and column definitions (such as number of columns and their data types) as the source table. However, data migration may still be possible even when their definitions are different if you use pdload's input data file (-W option specified) as the unload data.

Figure 8-7 provides an overview of migrating data to another table.

Figure 8-7 Overview of migrating data into another table

[Figure]

(3) Modifying table partitioning conditions

To modify table partitioning conditions, first save the table data to an unload data file, then modify the table partitioning conditions, and reload the data from the unload data file back into the table.

Figure 8-8 shows an overview of modifying table partitioning conditions.

Figure 8-8 Overview of modifying table partitioning conditions

[Figure]

(4) Using an unload data file as pdload's input data file or with a UAP

To use an unload data file as pdload's input data file or with a UAP, specify the -W option during unload operation.

(5) Unloading a table with LOB columns or abstract data type columns provided by a plug-in (LOB attribute)

As with table reorganization, you can unload a LOB column structure base table and LOB columns at the same time or separately.

(6) Unloading a table using a UOC

For details about unloading tables using a UOC, see 8.1.2 (5) Reorganization using a UOC.

(7) Using a utility special unit

For details about how to use a utility special unit, see Section 8.1.2 Reorganizing a table.