Stream Database


Synopsis

This operator reads an example set from an SQL database by incrementally caching it (recommended).


Description

This operator reads an ExampleSet from an SQL database. The data is load from a single table which is defined with the table name parameter. Please note that table and column names are often case sensitive. Databases may behave differently here.

The most convenient way of defining the necessary parameters is the configuration wizard. The most important parameters (database URL and user name) will be automatically determined by this wizard and it is also possible to define the special attributes like labels or ids.

In contrast to the DatabaseExampleSource operator, which loads the data into the main memory, this operator keeps the data in the database and performs the data reading in batches. This allows RapidMiner to access data sets of arbitrary sizes without any size restrictions.

Please note the following important restrictions and notes:

Beside the new index column or the mapping table creation no writing actions are performed in the database. Moreover, data sets built on top of a cached database table do not support writing actions at all. Users have to materialize the data, change it, and write it back into a new table of the database (e.g.with the DatabaseExampleSetWriter. If the data set is large, users can employ the operator BatchProcessing for splitting up this data change task.


Input


Output


Parameters


ExampleProcess