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 list them as Selected columns.
This step will only recognize the following system-defined tags:
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 which need to be compared. This is done to make the duplicate detection process more efficient. Blocks of records are created from using combinations of individual elements, to create a blocking key.
Every set of records in the resulting block is then compared using a ruleset, which is a set of logical expressions that controls the level of match which is returned.
Combinations of blocking keys and rulesets are stored in Step settings which can be selected in the Find duplicates step. To view the ruleset or blocking keys, or create a new set, go to Step settings > Find duplicates settings.
Aperture Data Studio provides default Find duplicates step settings for use with the Find duplicates step. The following default types of blocking keys and rulesets 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.
In particular, the default blocking keys and rulesets provided are 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 rulesets. The details of a step setting can also be viewed when clicked in the Step settings list screen.
You can retain your duplicate store to disk, so it can be used for searching and maintenance operations.
Duplicate stores are retained to your machine's Data Studio repository, within the
experianmatch sub-directory. However, if you have configured a separate instance of the Find duplicates server, duplicate stores will be retained on that same machine.
To retain a duplicate store when using the Find duplicates step:
Any duplicate store can be encrypted if you specify this before running the Find duplicates step.
Encrypting the store protects data whilst the step is running on disk and is especially important for duplicate stores that have been retained for later use. Non-retained stores are deleted after the step has completed but can still be protected while the results are being processed.