Library databases are searchable collections of literature (journal articles, newspapers, books, etc.), that allow you to identify resources for your research projects. Some databases are subject specific and some are very general (including all subjects).
Search several databases when beginning your project! There are unique references in each database you search.
You can 
using multiple email addresses, variations of your name, and your current and past affiliations, put your documents and records into one ID, and use the ID with databases such as Scopus and Web of Science so that you will not have to input your personal information again and again to maintain a current record.
You can also link to repositories, funding programmes, APIs and improve your publishing process.