Database information is seldom provided in reference list entries. The reference provides readers with the details they will need to perform a search themselves if they want to read the work—in most cases, writers do not need to explain the path they personally used.
Think of it this way: When you buy a book at a bookstore or order a copy off the internet, you do not write the name of the (online) bookstore in the reference. And when you go to the library and get a book off the shelf, you do not write the name of the library in the reference. It is understood that readers will go to their bookstore or library of choice to find it.
The same is true for database information in references. Most periodicals and books are available through a variety of databases or platforms as well as in print. Different readers will have different methods or points of access, such as university library subscriptions. Most of the time, it does not matter what database you used, so it is not necessary to provide database information in references.
However, there are a few cases when it is necessary for readers to retrieve the cited work from a particular database or archive, either because the database publishes original, proprietary content or because the work is of limited circulation. This page explains how to write references for works from academic research databases and how to provide database information in references when it is necessary to do so.
Database information in references is covered in the seventh edition APA Style manuals in the Publication Manual Section 9.30 and the Concise Guide Section 9.30