You can search statistical data on every fields by prefecture, which you have to  group together from huge collection of books and microfilms without this database.
For example, you can easily get the data like following:

- Transition of rice production by prefecture in Meiji period
- Number of teachers of a certain prefecture by sex and age in prewar period

[Contents]
0.9 million images, 1.5 million records of Prefectural Documents on Statistics (1873-1972)
 

J-STAGE is a platform for scholarly publications in Japan. It is developed and managed by the Japan Science and Technology Agency (JST). JST launched J-STAGE with the aim to:
- rapidly circulate research in science, technology, humanities and social sciences in Japan.
- strengthen the international dissemination of information from Japan to the rest of the world.
- promote the publication of open access content from Japan's academic societies and research organizations.

A fulltext database of medical journals published in Japan.

JAPAN COMPANY HANDBOOK is the basic company information magazine for job hunting. The first issue was published in 1936. This handbook can be used for comparing various type of industries and companies.

Available from 1936 issue 1 to 2016 issue 4.

This is the online database of Song Collection of Seikadou-Bunko Song Yuan Print Collection.

"Newspaper Clippingｓ　Collection " is the newspaper-clippings data from the end of Meiji to Showa 45. It was created by Research Institute for Economics and Business Administration, and is called "newspaper-clippings library". Newspaper articles had been collected over 60 years. The quantity is about 500,000 affairs and it is made into about 3200 volumes.

Detail: Colonization, agriculture, economy, society, political diplomacy, and education

NBDC provides many services to unite the database from the related associations.

AgriKnowlede is the comprehensive searching engine to search various data from many research institutes.

・papers about agriculture, forestry and fisheries.

・information about the research results from the institutes related with Ministry of Agriculture, Forestry and Fisheries.

CiNii Research, launched in April 2021, is an academic information search service provided by the National Institute of Informatics (NII).
It allows users to cross-search various information on research activities, including research data, articles, books, doctoral dissertations, and project information.

* CiNii Articles has been merged with CiNii Research on April 18, 2022.

Japan Platform for Patent Information offers the public access to IP Gazettes of the JPO free of charge through the Internet.