As the transformation you need to accomplish in ELT may exceed the scope of what the given SQL templates can achieve, Talend Studio allows you to develop your own SQL templates according to some writing rules. These SQL templates are stored in the UserDefined folders grouped according to the database type in which they will be used.
For more information on the SQL template writing rules, see SQL template writing rules.
To create a user-defined SQL template:
In the Repository tree view, expand SQL Templates and then the category you want to create the SQL template in.
Right-click UserDefined and select Create SQLTemplate to open the [New SQLTemplate] wizard.
Enter the information required to create the template and click Finish to close the wizard.
The name of the newly created template appears under UserDefined in the Repository tree view. Also, an SQL template editor opens on the design workspace, where you can enter the code for the newly created template.
For further information about how to create a user-defined SQL template and how to use it in a Job, see tMysqlTableList at https://help.talend.com.