Read DB table

This calculator step provides you with predefined functions that can be executed on input field values.

The execution speed of the Calculator is far better than the speed provided by custom scripts (JavaScript).

Besides the arguments (Field A, Field B and Field C) you must also specify the return type of the function. You can also choose to remove the field from the result (output) after all values are calculated; this is useful for removing temporary values.

The Number Range step in Pentaho Data Integration (PDI) maps numeric values to descriptive categories or ranges. This step takes numbers from an input field and assigns text descriptions based on which predefined range they fall into.

To use this step, you add it to your transformation, specify the input numeric field and output text field, then define your ranges with lower and upper bounds along with the corresponding description for each range. For example, you might categorize ages into groups like "Under 18," "18-24," "25-34," and so on.

This functionality is particularly valuable for data preparation, reporting, and visualization as it converts continuous numerical data into discrete, meaningful categories that are easier to analyze and understand. Common applications include creating age brackets, income ranges, temperature classifications, or performance tiers.

The Sort rows step sorts rows based on the fields you specify and on whether they should be sorted in ascending or descending order.

• Kettle must sort rows using temporary files when the number of rows exceeds the specified sort size (default 1 million rows). When you get an out of memory exception (OOME), you need to lower this size of change your available memory.

• When you use multiple copies of the step in parallel (on the local JVM with "Change number of copies to start" or in a clustered environment using Carte) each of the sorted blocks need to be merged together to ensure the proper sort sequence. This can be done, be adding the Sorted Merge step afterwards (on the local JVM without multiple copies to start or in the cluster on the master).

The Select Values step is useful for selecting, removing, renaming, changing data types and configuring the length and precision of the fields on the stream. These operations are organized into different categories:

Select and Alter

Specify the exact order and name in which the fields should be placed in the output rows.

Remove

Specify the fields that should be removed from the output rows.

Meta-data

Change the name, type, length and precision (the metadata) of one or more fields.

This transformation introduces several new steps that can help manipulate the data with predefined functions.