# Pattern validation components

| [tFindRegexlibExpressions](https://help.qlik.com/talend/r/en-US/7.3/components/pattern-validation/tfindregexlibexpressions) | Returns a dataset holding information about all of the regular expressions that<br>match the request sent to the web server. |
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| [tLastRegexlibExpressions](https://help.qlik.com/talend/r/en-US/7.3/components/pattern-validation/tlastregexlibexpressions) | Returns a dataset holding information about the N most recent regular expressions<br>added to the library and that match the query at [http://regexlib.com](http://regexlib.com/). |
| [tMultiPatternCheck](https://help.qlik.com/talend/r/en-US/7.3/components/pattern-validation/tmultipatterncheck) | Checks all existing data in multiple columns against a given Java regular<br>expression. |
| [tPatternCheck](https://help.qlik.com/talend/r/en-US/7.3/components/pattern-validation/tpatterncheck) | Gives two output flows: Matching Data and<br>Non-Matching Data. The first collects all data that match a given<br>pattern, and the second collects all data that do not match a given pattern. You can<br>then implement any required corrections. |