Uniform database interface

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The standardized data format for exchanging data in the geographic information systems used in Germany, the Automated Property Map (ALK) and the Official Topographic-Cartographic Information System (ATKIS), is called the uniform database interface ( EDBS ).

origin

EDBS was originally developed for the exchange of data from the Automated Property Map (ALK). This forms a visual part together with the automated guided book property ( ALB ), the real estate register. These efforts are comparable to the SDTS format of the US Geological Survey for the North American region.

Uniformly

The uniform attribute of this data interface has led to considerable irritation in some cases when it was spread on the market. From the point of view of the data user, this was linked to the expectation that the data transmitted would be uniform throughout Germany. However, this expectation could not be fulfilled by the official German land surveying and was not intended. In fact, the attribute stems from the fact that the data of the partial files of the ALK database part (point file, floor plan file, file of measurement elements, attribute file) can be output as a sequential, text-oriented file using a uniform mechanism. The data kept in the sub-files (and here in particular the selected object keys, line keys, design keys, etc.) could not, however, be consistently ensured due to different technical requirements in the countries.

In addition to this inconsistency in the content transmitted via EDBS, despite uniform structures, it should also be noted that the EDBS was not used by all land surveying administrations. In the ALK area, the EDBS format is used in North Rhine-Westphalia, Hesse, Lower Saxony, Schleswig-Holstein, Berlin, Brandenburg, Bremen, Rhineland-Palatinate, Saxony-Anhalt, Saxony, Thuringia and Mecklenburg-Western Pomerania.

ATKIS data are offered by all federal states in EDBS format.

This is not the case with the ALK / DFK: In Baden-Württemberg, data from the Land Surveying Office has so far been made available in SICAD-SQD format or BGRUND format [Baden 1990]. In Bavaria, in addition to the SQD format, the DFK interface format (DFK: Digitale Flurkarte ) is available [Bavaria 1993].

The data from the land surveying administrations form only part of the geographic information systems (GIS) - the so-called geographic base data - in Germany; In addition, there is a large number of geographic information from the application areas. To date, no interface standard that is generally applicable in Germany has been able to establish itself here.

construction

The EDBS was defined as part of the overall system "Automation of the property map" (ALK system). The structure is text-based, vector-oriented and includes the complete topology.

EDBS record contents are directly defined by the ALK / ATKIS database model.

An EDBS record consists of:

  • SA - record type "EDBS"
  • SL - record length consisting of the two parts 'length of the record' and 'start of the search criterion' (each 4-digit numeric)
  • OP - operation, 4 digits, e.g. B. "FEIN" (enter continuation), "FLOE" (delete continuation), "BSPE" (use of storage units = extract) etc.
  • QU - Acknowledgment and editing key (record number, sequence of records, "A" (start) - "F" (sequence) - "E" (end), with more than 2000 characters, confirmation key)
  • IN - information name, e.g. B. ULOBNN (OB = object file = floor plan), ULPUNN (PU = point file), ULTANN (ATKIS attributes)
  • II - information content according to IN
  • SK - search criterion, positioning of the DB cursor (e.g. when continuing objects), comparable to the Where-Clausel of SQL

z. B. EDBS01180000FEIN000019 0000ULOBNN 0001000144593923269836616847 00010001 ...

An EDBS job always begins with an AKND record (job identification data) and ends with an AEND record (job end). Several orders can occur in an EDBS file.

Line breaks LF (Unix) or CR + LF (DOS) are common separators between EDBS records.

The ALK / ATKIS database contains various files (or tables), for the processing of which different EDBS records are used (II). EDBS is basically used for updating or outputting the relevant files and maps the data structures of these files. A distinction is made between primary data and administrative data.

The user data is stored in the primary files. These include:

  • Floor plan file
  • Attribute file (only ATKIS)
  • Point file
  • Measurement elements file

There are also various administration files (at least in the ALK / ATKIS database version of the AdV). These are not processed or read out via EDBS, but via DBVS (database management interface):

  • Encryption files
  • Authorization file
  • Numbering district file
  • Subscriber secondary evidence (BZSN) administration
  • Database management

The vectors of the map image are saved in the floor plan file. Object formation is indispensable here. Lines are always saved including their function (e.g. parcel boundary, building edge, top edge of a slope, etc.) and their object affiliation (link via the seven-digit object number). Every object has an object coordinate. The ALK system knows point, line and area objects, in some federal states also frame objects (geometry without complete object formation). The ATKIS system also contains complex objects, a combination of several individual objects.

The contents of the floor plan file include:

  • Property number A999525
  • Object part number 1 (only ALKIS )
  • Property type 3102 (= path)
  • Slide 104
  • Object type L (inie)
  • Label point (3418315.94,5765981.04)
  • Date of origin 921123 (= 23 November 1992)
  • Starting point (3418583.34,5765292.92)
  • Endpoint (3418761.27,5765110.19)
  • Intermediate point (s) (3418644.90,5765115.08)

The attribute file contains factual data that is linked to floor plan objects. It only occurs in the ATKIS system.

The specific information for cataloging the individual measuring points, such as point number, point type (boundary point, building point, etc.), accuracy, date of creation, type of marking, file information, etc. is saved in the point file. The point file has mainly internal cadastral significance. A point can be stored in the point file in different coordinate systems (networks).

The measurement item file is not important. Additional information on measured points can be saved here as a supplement to the point file.

future

Work is currently underway to combine the Automated Property Map (ALK) and the Automated Property Book (ALB) in the standardized system of the Official Property Cadastre Information System (ALKIS). In the course of this change, the standards-based exchange interface (NAS) will be developed as the successor to EDBS on the basis of the XML standard .

ALKIS was originally to be introduced nationwide from 2007.

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