Steps

If you think that this is something you may wish to run as a Scheduled Job you would create a Workflow Job to run the Task to extract the data from the My Alerts database whenever you wish. 

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Select the Program Type and click OK.

Task Name

Enter a unique name for the task e.g. Extract My Alerts Email Addresses.

Program
Browse to the PostgreSQL interactive terminal executable which you will find in the installation folder for PostgreSQL e.g. C:\Program Files\PostgreSQL\n.n\bin\psql.exe where n.n is the version of Postgres you have installed.

Additional Parameters

Enter the following parameters:

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Please refer to the PostgreSQL documentation and , select the version of PostgreSQL you have installed and navigate to ViVI. Reference > PostgreSQL Client Applications > psql -- PostgreSQL interactive terminal for a definition of all the parameters.