The database describes three types of objects: the song, its printed form and the tune used.

The song is characterized by:

• Its reference: This is a number with no other meaning or function than that of the ranking guide, address. If, as happens, different variants of the song have different titles of origin, this will be the same for all these variants. Systematically, this number begins with "C" as "Chant" (e.g. C-00141).
• Its title: We will speak of the title of origin to designate the title printed on the broadsheet (or possibly variants of different titles according to the editions. In this case, the reference will mark this difference with a suffix (e.g. C-00141-1). Since the original titles are difficult to use (because of their length, their random spelling, the variations of titles according to the editions), it was necessary to create a standard title in Breton and in French. This standardized title tries to the maximum to be as short and meaningful as possible of the content of the singing. It is possible to query by any word or string of consecutive characters of the title. We will then get a list of all the songs containing that word or string.
• Its theme: see the list of themes in the query cartridge. This list includes the themes found in popular Breton folk songs of oral tradition enriched with those revealed by the analysis of the broadsheets and which did not appear in the oral tradition. The themes found exclusively in broadsheets are in fact few compared to the number of themes common to the two genera. Questioning according to theme makes it possible to obtain a list of songs which, when indexed, were considered to be relevant to the subject. Of course, a song can contain several different themes.
• Its summary: Summaries of a few lines in French have been made (or are being drafted) for each song. This allows for those who do not understand Breton to know "roughly" what the song is about and on the other hand to do research on words (search for a string of characters in full text). More often than not, essential words, equivalent to keywords, are found in the summary itself. In case of need, some keywords have been added as a result of the summary. So be careful to write the word in the singular.

A particular song can be found in different broadsheets, either they are different editions but contain the same series of songs:

• Or they are different editions but contain the same series of songs;
• Or they are different broadsheet containing different groups of songs from one broadsheet to another.

The print (broadsheet, booklet, handout...) can contain several different songs.
It is characterised by:

• Its reference (the "Malrieu reference" corresponds to the references of this database): As for song, it is a number with no other meaning or function than being a classification mark, an address. It always starts with "F" as "Feuille", e.g. F-00205. A particular reference is given each time the series of songs present on the broadsheet is different. For example, the songs C-00100, C-00101 and C-00102 can be
  • Either alone, each on a different broadsheet, we will then have so many different broadsheets, say F-00450/C-00100; F-00451/C-00101; F-00452/C-00102.
  • Or all three on the same broadsheet, we will then have broadsheet F-00453 containing C-00100 + C-00101 + C-00102.
  Any different sequence of songs in a broadsheet therefore generates a particular broadsheet reference.
  
  On the other hand, the different editions of a single broadsheet containing the same sequence of songs will only receive a suffix to mark the difference in editing. Thus the broadsheet F-00453 corresponding to the sequence C-00100 + C-00101 + C-00102 will be called F-00453-1 for one edition and then F-00453-2 for another edition of the same sequence of songs. It doesn't matter if this different edition was made by the same printer or by another one. Sometimes the difference between one edition and another is due to minimal details of typography, for example, or cul-de-lamp/tail-piece, or rule… but each of these details shows a particular reprint of this broadsheet and therefore of the diffusion it has known in the population.
  
  It is also possible to search by questioning according to the given number in the Ollivier catalogue, the "reference Ollivier", which we have already pointed out in the general comments of the Ollivier catalogue. Its generalized use over 70 years justifies the possibility of questioning the basis by this criterion.
  For the realization of this database, it was necessary to assign a different numbering than that established by Joseph Ollivier. Indeed, the principles chosen by J. Ollivier were not easily compatible with the constraints of computer processing:
  • Essentially, the mixture of the notion of "song" and the notion of "broadsheet" J. Ollivier’s need to give suffixes (nnn-A, B, C, D) when the same song was in broadsheets with different song sequences.
  • Some rare errors (the same song registered under different references)
• The Printer’s signature: The mention of the name of the printer is often found on the last page of the broadsheet (sometimes even at the end of each song of the broadsheet).
  On the one hand, this signature can be ambiguous insofar as the printer is often also the publisher of the broadsheet, or sometimes the author. In some cases, people (different from the printer and the author) seem to have bought the publishing rights and are reputed "owners" of the broadsheet... Anyway this signature is often a source of multiple information:
  • concerning the date (rarely)
  • concerning the address which may allow the broadsheet to be dated approximately the broadsheet according to what is known of the printer's installation periods at a particular location, or its dates of activity.
  • concerning variations between editions.
  See the printed notices that give information mainly from the Ollivier catalogue.

The tune is the air on which it is proposed to sing the text, the name of another song known and considered to be well-known. A given song may be, according to different broadsheets, proposed with different tunes.

The authors ' notes give information mainly from the Ollivier catalogue and the Lukian Raoul dictionary (see Bibliography).
As with the titles, it was necessary to standardize the names of the authors.
In fact, in the document itself, a single author can appear in multiple forms: spelling variants, name in French or Breton, various pseudonyms, simple mention in the text or index allowing knowing who is the author without revealing his name clearly.

Moreover, the notion of copyright being very random at the time, it is possible to find the same song imputed to different authors, without it being always possible to know who copied who.

However, it was also necessary to allow questioning by original author (i.e. as printed on the broadsheet). Indeed, except to oblige the consultant to look in a standardized name or pseudonym equivalency table, not everyone knows that Ann Uhel = Luzel, for example or that Bleiz Lanvauz = the Abbot Marshal.


In addition, for any textual search:

• The search is done by character string in the strict sense (replies to "Brezel 1914" are not those of "1914 Brezel").
• It is possible to use a truncation (*) to replace a letter, word, or group of words.
• It is not possible to search with Boolean operators of the type AND, OR, EXCEPT.