This section covers key concepts related to the Find duplicates step.
A cluster is a collection of records that have been identified as representing the same entity using the Find duplicates rules. Each cluster is identified by a unique cluster ID.
Each match between two records will have one of the following confidence levels:
|Exact (0)||Each individual field that makes up the record matches exactly.|
|Close (1)||Records might have some fields that match exactly, and some fields that are very similar.|
|Probable (2)||Records might have some fields that match exactly, some fields that are very similar, and some fields that differ a little more.|
|Possible (3)||Records contain the majority of fields that have a number of similarities, but do not match exactly.|
|None (4)||Records do not match.|
If your data has columns tagged already, this step will recognize the tagged columns and automatically assign a relevant Find duplicates column mapping to them. Otherwise, you can manually assign the column mappings based on your knowledge of the data.
This step will only recognize the following system-defined tags:
It is important to map your columns as accurately as possible before using the Find duplicates step to make the matching process more efficient. For example, mapping a column as Address when it contains primarily company or name information will lead to less accurate results.
Additionally, using the more granular address element mappings such as Premise and Street and Locality as opposed to the higher level Address mapping (providing your data is divided in such a way) will mean that less effort is required to identify individual address components.
For more information on how Find duplicates utilizes these column mappings, you can refer to the advanced configuration page.
You can apply different rulesets to columns with the same tag by using group IDs.
For example, you may have delivery and billing addresses that you want to treat differently. You would tag both as an address, but create separate group IDs, allowing you to apply different rulesets: only accept an exact match for the billing address, but a close one for the delivery address.
The Find duplicates step first creates blocks of similar records, which reduces the number of records that need to be compared. This is done to make the duplicate detection process more efficient. Blocks of records are generated based on a blocking key, which is made up of a combination of record elements.
Every pair of records in the resulting block is then compared using a set of rules, which are logical expressions that control the match level returned.
Combinations of blocking keys and rules are stored in Step settings which can be selected in the Duplicate store configuration when using a persistent store, or in the Find duplicates step. To view the rules or blocking keys, or create a new set, go to Step settings > Find duplicates settings, or from the Duplicate stores screen either click Create new Duplicate store or select the Edit details action on an existing Duplicate store.
Aperture Data Studio provides default Find duplicates step settings for use with the Find duplicates step. The following default types of blocking keys and rules are available by navigating to Step settings > Find duplicates settings:
GBR_Individual_Defaultwill find individuals in Great Britain. Note that emails, phone numbers, and other identifiers will not be taken into account, but can be added manually.
GBR_Household_Defaultwill find households in Great Britain.
GBR_Location_Defaultwill find locations in Great Britain.
Default blocking keys and rules are provided for Australia (AUS), Great Britain (GBR), and United States (USA) as detailed in the table below:
|AUS_Individual_Default||Default Australia individual level rules and blocking keys based on name and address|
|AUS_Household_Default||Default Australia household level rules and blocking keys based on surname (last name) only and address|
|AUS_Location_Default||Default Australia location level rules and blocking keys based on address only|
|GBR_Individual_Default||Default United Kingdom individual level rules and blocking keys based on name and address|
|GBR_Household_Default||Default United Kingdom household level rules and blocking keys based on surname (last name) only and address|
|GBR_Location_Default||Default United Kingdom location level rules and blocking keys based on address only|
|USA_Individual_Default||Default United States of America individual level rules and blocking keys based on name and address|
|USA_Household_Default||Default United States of America household level rules and blocking keys based on surname (last name) only and address|
|USA_Location_Default||Default United States of America location level rules and blocking keys based on address only|
The summary of each step setting is included to explain the purpose of the blocking keys and rules. The details of a step setting can also be viewed when clicked in the Step settings list screen.