Environmental Data Archive - Data description

The EDMS application queries a schema completely independent of the file database. This catalogue is populated with a subset of the data archived in files and all relevant metadata needed to extract the data, such as the spatio-temporal coordinates and the data type description. The information is organized in the following way:

  • Environment: Physical environment where the data were collected (hydrosphere, atmosphere, benthic zone).
  • Datatype: File type in which the data is archived.
  • Subdatatype: How the data was collected.
  • Variable : Description and units of the data.
  • Data: Data value.

The EDMS schema is detailed below. Each level of information is represented by one or two EDMS tables with the exception of the Data level, which is divided into as many DONNEES_* tables as there are distinct Subdatatype. For example, DONNES_CTD holds CTD profile data, DONNEES_BOTL holds discrete data from seawater sampling bottles, DONNEES_ADCP holds data on seawater currents measured with a moored ADCP device, and so on. A DONNEES_* table has a certain number of metadata columns such as latitude (LATD), longitude (LOND), depth (DEPH), and date-time (SYTM) of the measurement in addition to the data (Variable) columns, which could include variables such as temperature (TE90) and salinity (PSAL).

Table contents are as follows:

ENVIRONMENT table (subset of MILIEU table)

ACR_MILIEU NOM_EN DESCRIPTION_EN (...)
EAU Hydrosphere Aquatic environment (...)
AIR Atmosphere Atmospheric environment (...)
BEN Benthosphere Benthic environment (...)

DATATYPE table (subset of TYPE_DONNEES table)

ACR_TYPE ACR_MILIEU COMMENTAIRE
BOTL EAU Bouteille
CTD EAU CTD
MADCP EAU ADCP mouillé
(…) (…) (…)

SUBDATATYPE table (subset of SOUS_TYPE_DONNEES table)

ACR_TYPE ACR_SOUS_TYPE ACR_MILIEU NOM_TABLE NOM_FR DESCRIPTION_FR (...)
BOTL BOUTEILLES EAU donnees_bouteilles Bouteille Données de bouteille/Rosette. (...)
CTD CTD EAU donnees_ctd CTD Données de CTD. (...)
MADCP ADCP_MOUILLE EAU donnees_adcp ADCP mouillé Données de mouillage d`ADCP. (...)
(…) (…) (…) (…) (…) (…)  

VARIABLE table (subset of VARIABLE table)

ACR_VARIABLE NOM_EN DESCRIPTION_EN (...)
PSAL Salinity Water practical salinity [PSU] (...)
TE90 Temperature Water temperature (ITS-90 scale) [degrees C] (...)

CTD DATA table (subset of DONNEES_CTD table)

DONNEES_
CTD_SEQ
SEQ_JD NO_LIGNE LATD LOND DEPH SYTM TE90 PSAL (…)
4219253 179276 1 48,8084 -68,2361 2 2014-11-20 15:15 2,229 25,67 (…)
4219254 179276 2 48,8084 -68,2361 3 2014-11-20 15:15 1,989 25,61  
4219255 179276 3 48,8084 -68,2361 4 2014-11-20 15:15 2,060 25,68  
4219256 179276 4 48,8084 -68,2361 5 2014-11-20 15:15 2,051 25,80  
4219257 179276 5 48,8084 -68,2361 6 2014-11-20 15:15 2,037 25,88  
4219258 179276 6 48,8084 -68,2361 7 2014-11-20 15:15 2,068 26,03  
4219259 179276 7 48,8084 -68,2361 8 2014-11-20 15:15 2,082 26,27  
4219260 179276 8 48,8084 -68,2361 9 2014-11-20 15:15 2,070 26,41  
4219261 179276 9 48,8084 -68,2361 10 2014-11-20 15:15 2,063 26,48  
4219262 179276 10 48,8084 -68,2361 11 2014-11-20 15:15 2,044 26,57  
4219263 179276 11 48,8084 -68,2361 12 2014-11-20 15:15 2,012 26,76  
4219264 179276 12 48,8084 -68,2361 13 2014-11-20 15:15 1,964 27,02 (…)

EDMS Schema

In the schema above, tables are named using "SGDO" tags; the EDMS was developed as part of another schema called SGDO due to computer limitations.

In the EDMS schema, the orange tables are those described above, the blue table is the CTD profile table (one of several data tables, DONNEES_*), and the yellow tables hold further information concerning the spatial details of the sampling (TYPE_TRACK table) and the sampling survey during which the data were collected (SOUS_TYPE_DONNEES_MISSION_JD table). The spatial nature of a data set is used any time the application displays the location on a map; it can be a point, a rectangular area, a linear track, or an area of any shape.

The data set sequence number (SEQ_JD) is exactly the same in both the file archive system and the EDMS. From a database point of view, these sequence numbers are not related to each other, but in fact, this important feature is used by data managers to keep track of a data set since the SEQ_JD is the only link between the EDMS and the file catalogue.

The description of table columns may be viewed by following this link: EDMS Tables [French only]