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RegEx Check

The RegEx Check processor checks the data in an attribute against reference lists of valid and invalid regular expressions for the attribute.

The case-sensitivity and matching technique (Whole Value / Contains / Starts With / Ends With) of the check can be controlled.

Note on Regular Expressions

Regular expressions are a standard technique for expressing patterns and manipulating Strings that are very powerful once mastered.

Tutorials and reference material about regular expressions are available on the Internet, including:

Regular Expressions Info

and in books, including:

Mastering Regular Expressions by Jeffrey E. F. Friedl published by O'Reilly UK; ISBN: 0-596-00289-0.

There are also software packages available to help you master regular expressions, such as RegExBuddy, and online libraries of useful regular expressions, such as RegExLib.

Use

The RegEx Check processor is a powerful tool, allowing you to validate data according to its exact content, using the position of data, partial and exact values, and wild cards.

The RegEx Check is useful in order to check any data that should be in a consistent structure, for example, UK National Insurance Numbers.

The following are some examples of regular expressions that might be used to check data:

Regular Expression	Pattern meaning
^\d{5}$	5 integer US zip code
([A-Z]{1,2}[0-9]{1,2}\|[A-Z]{3}\|[A-Z]{1,2}[0-9][A-Z])( \|-)[0-9][A-Z]{2}	Valid UK Postcode
^[A-CEGHJ-PR-TW-Z]{1}[A-CEGHJ-NPR-TW-Z]{1}[0-9]{6}[A-DFM]{0,1}$	Valid UK National Insurance number
^([a-zA-Z0-9_\-\.]+)@([a-zA-Z0-9_\-\.]+)\.([a-zA-Z]{2,5})$	Valid email address

Many more examples are available on the Internet and from other sources.

Configuration

Inputs

A single attribute that you wish to check based on lists of valid and invalid regular expressions (or both).

Options

Valid patterns

Option	Type	Purpose	Default Value
Reference Data	Reference Data (Regular Expressions Category)	List of valid regular expressions for the attribute	None
Regular expression	Free text	Allows a single regular expression for valid patterns to be specified without using Reference Data. Note that if this option is used as well as Reference Data, all regular expressions (in both options) are used in the check.	None
Categorize unmatched as	Selection (Unknown/Invalid)	How to categorize values that do not match the list of valid regular expressions	Unknown

Invalid patterns

Option	Type	Purpose	Default Value
Reference Data	Reference Data (Regular Expressions Category)	List of invalid regular expressions for the attribute	None
Regular expression	Free text	Allows a single regular expression for invalid patterns to be specified without using Reference Data. Note that if this option is used as well as Reference Data, all regular expressions (in both options) are used in the check.	None
Categorize unmatched as	Selection (Unknown/Valid)	How to categorize values that do not match the list of regular expressions	Unknown

Match options

Option

Type

Purpose

Default Value

Ignore case?

Yes/No

Drives whether or not to ignore case when matching the list(s)

Yes

Match list by

Selection

(Whole Value/Contains/Starts With/Ends With)

Drives how to match against the list(s)

Whole Value

Outputs

Data attributes

None

Flags

Flag attribute	Purpose	Possible Values
RegExValid	Indicates which data passes the RegExCheck: Valid RegEx, Invalid RegEx and Unknown.	Y/N/-

Publication to Dashboard

A RegEx Check's results may be published to the Dashboard.

The following interpretation of results is used by default:

Result	Dashboard Interpretation
Valid	Pass
Unknown	Warning
Invalid	Alert

Execution

Execution Mode	Supported
Batch	Yes
Real time Monitoring	Yes
Real time Response	Yes

Results Browsing

The RegEx Check produces a summary view of its results, showing the following statistics:

Statistic	Meaning
Valid records	The records that were categorized as Valid by the RegEx Check.
Unknown records	The records that were categorized as Unknown by the RegEx Check.
Invalid records	The records that were categorized as Invalid by the RegEx Check.

Drilling down on any of the above statistics reveals a count of the distinct values that were found to be Valid, Unknown or Invalid. You can then drill down again to see the records themselves.

Output Filters

The following output filters are available from a RegEx Check:

Valid records
Unknown records
Invalid records

Example

In this example, a RegEx Check is used to check the format of an Account Number attribute (CU_ACCOUNT), using a Whole Value match against the following regular expression:

^([0-9]{2})(-)([0-9]{4,5})(-)([a-zA-Z]{2})

This regular expression dictates that values must start with exactly 2 digits, following by a hyphen, followed by either 4 or 5 digits, followed by another hyphen, followed by two letters.

Summary View

Drilldown on Invalid Records

Note that in this case a few records were found with OO (two capital letter Os) instead of 00 (two zeros).