Literary databases allow you to search by the named worked and named author. This is different from how you would normally search in other databases. If you run an author search in Super Search, and choose the author index, you will find works BY that author. If you search using the subject index, you find works ABOUT that author. If you search using the title index, you will find that work. If you search using the subject index, you will find analysis and critiques OF that work. When you use the keyword index (that's the default for databases), you'll get a combination of results that may include works by the author, the work itself and works about the author and/or the work.
On the other hand, databases devoted to literature give you the means to search both work and author because they know that's what researchers are looking for.
A primary source is the work itself being discussed, and also, in research, materials written or created about it during the time period in which it was created. Primary works can include initial publication book reviews, diaries and letters, manuscript drafts, communication with publishers and collaborators, interviews, and speeches.
You can find books and articles and limit their publication date to your chose writer's time period using SuperSearch. The JSTOR peer reviewed journal collection is especially helpful because it offers historic coverage going back to first issues of journals. So you can find early reactions to Sylvia Plath's The Bell Jar as well as interviews of contemporary writers.
In SuperSearch, use the advanced search to search by an author/creator to find his/her works and possibly collections of letters and other primary materials by that author. Using the keyword search finds everything associated with that author: both primary and secondary, and even tertiary items, which include encyclopedia entries and give the broadest overviews.
These include critiques and analysis not from the lifespan or shortly thereafter of a writer, or more broadly, the time period of a literary movement. Journal articles and books that provide overviews fall into this category. Analyses of a particular work or an author's ouevre over time- theoretical treatments using a cultural or political framework, such as New Historicism, feminism, colonialism, ecocriticism, or postmodernism, offering the author's interpretation, are secondary sources. In Super Search, you can narrow down your results by subject, or use the Advanced Search to search your author as a subject.
Reference materials are compilations of secondary and primary sources about authors, works, and literary movements. They consist of biographies, historical timelines, and compilations, such as anthologies similar to survey texts, and books such as Dictionary of Literary Biography and the Twayne's Author Series. While these provide substantial background information, and can include full book chapters of analysis (secondary sources) or excerpts from peer reviewed journal articles, it's best to use these in tandem with primary and secondary materials. Information from reference sources is designed to provide context for further exploration of a topic.