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The table below describes the features available for configuring the stream lookup:

Option

Description

Step name

Name of the step this name has to be unique in a single transformation

Lookup step

The step name where the lookup data is coming from

The keys to lookup...

Allows you to specify the names of the fields that are used to look up values. Values are always searched using the "equal" comparison

Fields to retrieve

You can specify the names of the fields to retrieve here, as well as the default value in case the value was not found or a new field name in case you didn't like the old one.

Note: The Type of the Default value does only provide the data type for the conversion of the Default value. It does not convert the original type of the field.

Preserve memory

Encodes rows of data to preserve memory while sorting. (Technical background: Kettle will store the lookup data as raw bytes in a custom storage object that uses a hashcode of the bytes as the key. More CPU cost related to calculating the hashcode, less memory needed.)

Key and value are exactly one integer field

Preserves memory while executing a sort by . Note: Works only when "Preserve memory" is checked. Cannot be combined with the "Use sorted list" option.
(Technical background: The lookup data is stored in a custom storage object that is similar to the byte array hashmap, but it doesn't have to convert to raw bytes. It just takes a hashcode of the long.)

Use sorted list

Enable to store values using a sorted list; this provides better memory usage when working with data sets containing wide row. Note: Works only when "Preserve memory" is checked. Cannot be combined with the "Key and value are exactly one integer field" option. (Technical background: the lookup data is put into a tuple and stored in a sorted list. Lookups are done via a binary tree search.)

Get fields

Automatically fills in the names of all the available fields on the source side (A); you can then delete all the fields you don't want to use for lookup.

Get lookup fields

Automatically inserts the names of all the available fields on the lookup side (B). You can then delete the fields you don't want to retrieve

Metadata Injection Support

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