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Documentation/DataLoadEngine/RegexRedactions.md

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+# Regex Redactions
+
+RDMP has the ability to redact incoming and existing catalogue data.
+It uses user-defined regex to do this.
+This functionality may be useful if you know about problematic data that you wish to clean before it reaches RDMP
+
+## Setup & Configuration
+To begin, a redaction configuration is required.
+This can be added in the "Configurations" section of RDMP.
+Each configuration has:
+* A Name
+* A Description
+* A Regex string to match
+* A Replacement value
+
+N.B. The replacement value cannot be longer than the redacted string i.e. "string" => "myRedactedString" will not work.
+
+Once the configuration has been saved, it can be used to redact data.
+
+## Usage in Data Loads
+Within the Data Loads mutilators, there is a mutilator named "Regex Redaction Mutilator" that can be used in the RAW or STAGING areas of the load.
+This mutilator will redact based on your selected configuration.
+The configuration for this mutilator requires:
+* A predefined regex redaction configuration (see above)
+* Either a regex to select which columns to redact, or a selection of known columns
+
+N.B. Primary Key columns will not be redacted and this functionality is intended for string fields.
+
+Once the configuration has been set, it will redact the desired columns during a data load.
+
+During a run, the mutilator will replace any regex matches with the desired string and store the now known redaction in RDMP.
+To view the redactions made, see the section below.
+
+
+## Usage within RDMP
+You can view and restore existing redactions, along with adding new redactions within RDMP.
+For a Catalogue, right-click and iopen the "Catalogue Items" submenu. 
+From here, select the "Regex Redactions" option.
+This will open an interface displaying existing redactions.
+From here you casn restore existing redactions either individually or in bulk.
+Yuo can also apply regex redactions to existing data by selecting a redaction configuration and which columns to redact.