# Editing a regular expression or a SQL pattern

Available in...

* Big Data Platform
* Cloud API Services Platform
* Cloud Big Data Platform
* Cloud Data Fabric
* Cloud Data Management Platform
* Data Fabric
* Data Management Platform
* Data Services Platform
* Qlik Talend Cloud Enterprise Edition
* Qlik Talend Cloud Premium Edition
* Real-Time Big Data Platform

You can open the editor of any regular expression or SQL pattern to check its settings and/or edit its definition in order to adapt it to a specific database type, or adapt it to a specific use.

## Before you begin

You have selected the Profiling perspective.

## Procedure

1. In the DQ Repository tree view, expand Libraries > Patterns.
2. Browse through the regular expression or SQL pattern lists to reach the expression or pattern you want to open/edit.
3. Right-click its name and select Open from the contextual menu.

   The pattern editor opens displaying the regular expression or SQL pattern settings.

   The pattern editor opens displaying the regular expression or SQL pattern settings. ![Overview of the Pattern Metadata and Pattern Definition sections.](https://help.qlik.com/talend/en-US/studio-user-guide/Resources/images/Pattern_open1.png)
4. Modify the pattern metadata, if required, and then click Pattern Definition to display the relevant view.

   In this view, you can: edit pattern definition, change the selected database and add other patterns specific to available databases through the [+] button.

   Information noteNote:

   For the PostgreSQL database, regular expressions are not compatible among the database different versions.

   If you want to use the regular expression with PostgreSQL version 12 or greater, you must either:
   * In the PostgreSQL database configuration, set the standard\_conforming\_strings parameter to off and write double backslashes in the definition.
   * In the Regular expression field in the wizard, use a single backslash in the expression definition.

   For further information about PostgreSQL regular expressions, select Window > Show View, expand Help and then select Bookmarks.
5. If the regular expression or SQL pattern is simple enough to be used in all databases, select Default in the list.
6. Click the save icon on top of the editor to save your changes.

   Information noteNote: When you edit a regular expression or a SQL pattern, make sure that your modifications are suitable for all the analyses that may be using this regular expression or SQL pattern.