• User Guide
  • Our Services
  • Tokyo Main Library
  • Kansai-kan of the NDL
  • International Library of Children's Literature
  • Access
  • Photoduplication Service
  • User Registration
  • Online Services
  • List of Online Services
  • Legislative Information
  • Online Catalog
  • Digital Library
  • Search Guide
  • Online Gallery

Top > Frequently asked questions > Searching, Reading for materials, Researching > About databases

Frequently asked questions : About databases

Frequently asked questions

To the head of this page

Q
What can I search by the NDL-OPAC ?
A
You can search for the materials held by the NDL, including books, periodicals and newspapers published inside and outside Japan, electronic resources, rare books and old materials, doctoral dissertations, maps, audio-visual materials, standards and technical reports. The Japanese Periodicals Index can also be searched via the NDL-OPAC. For details, please refer to "NDL-OPAC help."

To the head of this page

Q
What is the difference between NDL Search and NDL-OPAC?
A
Since NDL-OPAC searches only for materials in the National Diet Library holdings, it is useful when searching for National Diet Library's collections or when applying for remote copying services.
In contrast, NDL Search runs integrated searches for materials from the collections of various institutions across Japan, including public, university, and special libraries, as well as archives, museums, and academic research institutions.

To the head of this page

Q
Are all articles from periodicals searchable in the Japanese Periodicals Index (JPI)?
A
Only articles published in periodicals selected and indexed by the Library in the JPI (indexed periodicals) are searchable. For names of periodicals and the start and stop dates of indexing for periodical issues, please check the "List of Indexed Periodicals in the Japanese Periodicals Index" (in Japanese). Selection of indexed periodicals is conducted in accordance with the "Japanese Periodicals Index Periodical Selection Criteria". In addition to this, selection of articles in selected and indexed periodicals is conducted in accordance with the "Japanese Periodicals Index Article Selection and Indexing Criteria". Please note that the scope of indexed periodicals has changed over time.

To the head of this page

Q
Am I able to read digitized materials from articles I've searched in the Japanese Periodicals Index (JPI)?
A
For periodical articles that list “Digital Data” as their collection location in the Holdings or bibliographic information of NDL-OPAC, you may read these as digitized materials only within the Tokyo Main Library, the Kansai-kan Library, and the International Library of Children's Literature.

Using a Library terminal, when you click on the “Digitized Contents” button displayed in the Holdings or Bibliographic Information of NDL-OPAC, the text of the periodical will be displayed as a digital image.
In some cases, the “Digitized Contents” button may not appear even though the collection location is listed as “Digital Data.” In such cases, the text will be readable if you perform a search by article name etc. in the NDL Digital Collections.

To the head of this page

Q
Please increase the number of periodicals searchable in the Japanese Periodicals Index (JPI).
A
The JPI has consistently expanded its indexed periodicals up to this point. At present, the JPI lists about 10,000 academic journals, technical journals, and general interest magazines. The number is being expanded on a regular basis by selecting newly published periodicals.
For names of periodicals and the start and stop dates of indexing for periodical issues, please check the "List of Indexed Periodicals in the Japanese Periodicals Index" (in Japanese). Selection of indexed periodicals is conducted in accordance with the "Japanese Periodicals Index Periodical Selection Criteria".

To the head of this page