The Loader provides you with functions for unloading, loading, and formatting data between different data sources and data targets using data streams.
This action is known as a transformation and is described using entries in the Loader-specific system tables.
The Loader uses metadata, which can be in different formats, for the logical description of data and its transformation. When the system tables of the Loader are filled, this can, among other things, be used for restarting a transformation.
The range of language of the Loader allows transformation of the data for all users of a database, a user, a table of a user, or a set of qualified columns of a table or multiple tables. Loader commands are provided for these purposes.
Media and database instances are supported as physical data sources and physical data targets.
The entire database catalog and all the application data can also be unloaded or loaded using external backup tools.
A transformation is identified using Loader and database instance details, a transformation type, the required part of the database catalog, and the data streams.
·
Loader
connection:
Server node, database name, user name, password, SQL mode, ASCII code page,
transaction size, MaxErrorCount, backup tool
·
Database
connection:
Server node, database name
·
Transformations
type:
EXTRACT: Data is to be unloaded.
LOAD: Data is to be loaded.
UPDATE Data is to be changed.
·
Part of the
database catalog:
You can define the scope of the database catalog objects of a database
instance involved in a transformation.
ALL: Entire database catalog
USER: Part of the database catalog that belongs to the specified user
TABLE: Part of the database catalog that belongs to the specified table
You can specify a set of qualified columns of one or more tables.
You can determine the commands and their runtime information from the system
tables for the parts of the database catalog specified using ALL and
USER.
· Data stream