3. Database Organisation

This historic document provides information about the lineage of some Landonline cadastral data. The information is as published prior to the creation of Landonline.

Within VISION* the schema definition of a database refers to the format and organisation of the user attribute tables as well as the specification of any topological structures such as layers and networks.

The database schema used for DCDB allows us to organise our data in a logical manner which will help simplify and clarify data relationships, and facilitate the users understanding and analysis of the data.

The database schema provides the specification for layers, networks and the definition of feature codes and the user attributes associated with them.

3.1. Explanation of Schema

3.1.1. Layers

The DCDB schema consists of six data layers as outlined under List of User Defined Layers

These layers are used to group features, and networks, which are associated by the type of information they portray, for example, the Stats/Admin Layer only contains feature codes and networks related to statistical and administrative information.

Layers are the second level of the database structure with the map or database being the first level.

The layer structure can be used to assist the management of information in the database. For example, the Content Maintenance facility (cdm) enables various controls to be placed upon the use of information in the database at a layer level. Other programs like gina_out enable data processing to be restricted to selected layers of information.

Symbolisation of data within VISION* can also be controlled at a layer level.

List of User Defined Layers

Layers:
Layer number:
Cadastral
100
District
101
Strata
102
Statute
103
Stats/Admin
104
Plan Reference
106
Layer Description:Cadastral informationLand District
Information
Strata
Information
Statutory RestrictionsStatistical and
Administration Polygons
Plan Reference
Information
CommentsAll cadastral boundary
and Road Information
-To store a definition
of Strata plans
Proclamations
of central government importance
Meshblock boundary and
identifier information
All Plan references
and provisional plans

3.1.2. Networks

These are the next level of the structure below the layers and are further subdivision of the features, contained on a layer, into sub-groups. For example, the Cadastral Layer is divided into seven networks. Networks exist as outlined under List of User Defined Networks.

Each network enables the grouping of features which have some geometrical connectivity or geometrical relationships. Which features are physically connected to other features or which features are next to other features, is known as topology.

Networks may be of two types: Polygon or Linear.

Polygon networks are networks that topology can be created within. A polygon is a closed feature, for example, a parcel of land with topology formed. To form topology and hence create a polygon, a centroid identifier must be placed within the parcel's boundaries, then a relationship between the centroid identifier and the boundaries can be established (topology formation).

Linear networks are networks that only store line or point features which are not intended to form polygons. The lines within these networks may be inter-connected such as on the centrelines network or they may be randomly scattered such as private road boundaries on the private roads network. The relationship between networks and layers is shown in the following diagram.

List of User Defined Networks.

LayersCadastral
100
District
101
Strata
102
Statute
103
Stats/Admin
104
Plan Reference
106
NetworksSurvey
1000
Land
1011
Parcel Strata
1020
Proclamation
1032
Meshblock
1040
Plan
1060
 Partition
1002
   Ward
1043
 
 Centreline
1005
   TA
1044
 
 Road Legality
1006
   Region
1045
 
 Address
1007
   Constituency
1046
 
 Survey Maint
1008
   General
1047
 
 EMF
1009
   Maori
1048
 
     No Licence
1049
 

NOTE - The Statute layer (103) and Survey Maint network (1008) are not available for client supply.

3.2. Schema Features

The fundamental database spatial entity is called a feature. A feature has one or more coordinates, an optional graphic text string, optional graphic parameters, (text size and justification for example), system attributes, (feature code, layer and network number, length for example), and optional user defined attributes (appellation, plan number and street address for example). The feature code determines which symbolisation is to be used for a feature, and also determines which attribute table is used for the user defined attributes directly associated with the feature.

The DCDB schema uses three types of features namely: Polygon, Linear, and Point.

The list below shows the features defined in the schema, their type and definition:

FeaturePrimary TableTypeDefinition
access_clroad_clLinearCentreline defining accessways
addressaddressPointAddress feature (Road name and property number)
constituencyconstituencyPolygonRegional Constituency polygon centroid
constit_bdyp_sufiLinearBoundary defining Regional Constituency derived from meshblocks.
easement_clcovenantLinearCentreline defining easement in gross
emfemfPointEnd point marker feature defining source of data
emf1008emfPointMaintenance end point marker feature defining source of data - Not for client supply
generalgeneralPolygonGeneral Electorate polygon centroid
general_bdyp_sufiLinearBoundary for General Electorate derived from meshblocks.
hyd_segmenthyd_segmentPolygonHydrographic polygon centroid
h_linep_sufiLinearLine used to close off cadastral hydrographic features to ensure polygons are formed. eg. river confluence, river mouth.
land_distland_districtPolygonLand district polygon centroid
ld_bdyp_sufiLinearLand district polygon boundary
m_part_bdyp_sufiLinearParcel boundaries derived from unsurveyed Maori partitions.
maorimaoriPolygonMaori Electorate polygon centroid.
maori_bdyp_sufiLinearBoundary for Maori Electorate derived from meshblocks.
maint_bdyp_sufiLinearMaintenance data - Not for client supply
mesh_bdyp_sufiLinearMeshblock boundary feature code cloned from current cadastral boundaries or centrelines. This feature code is used in all client supply.
mesh_cadp_sufiLinearMeshblock boundary following, or derived from, current cadastral boundaries.
mesh_topop_sufiLinearMeshblock boundary following, or derived from, current topographic features.
mesh_otherp_sufiLinearMeshblock boundary following, or derived from, features which are unknown, poorly defined or no longer current.
meshblockmeshblockPolygonMeshblock polygon centroid.
no_licenceno_licencePolygonAlcohol No Licence District Polygon centroid derived from meshblocks.
no_lic_bdyp_sufiLinearBoundary for Alcohol No Licence District.
parcelparcelPolygonParcel polygon centroid
parcel02parcelPolygonMaori partition parcel polygon centroid
parcel20parcelPolygonStrata parcel polygon centroid
parcel32parcelPolygonProclamation parcel polygon centroid
parcel1008parcelPolygonMaintenance parcel polygon centroid - Not for client supply
parcel_arcp_sufiLinearParcel Arc boundaries. Parcel boundaries which are also arcs.
parcel_arc02p_sufiLinearMaori partition parcel Arc boundaries. Parcel boundaries which are also arcs. Cloned from parcel_arc
parcel_arc20p_sufiLinearStrata parcel Arc boundaries. Parcel boundaries which are also arcs. May be cloned from parcel_arc
parcel_bdyp_sufiLinearParcel boundaries derived from survey plans.
parcel_bdy02p_sufiLinearMaori partition parcel boundaries derived from survey plans. Cloned from parcel_bdy
parcel_bdy20p_sufiLinearStrata parcel boundaries derived from survey plans. Maybe cloned from parcel_bdy
parcel_hydp_sufiLinearSurveyed stream/river/lake/coastline edges which are also legal parcel boundaries.
parcel_hyd02p_sufiLinearSurveyed stream/river/lake/coastline edges which are also legal Maori partition parcel boundaries. Cloned from parcel_hyd
plansurv_planPointPlan feature
plan_provsurv_planPointProvisional plan feature
proc_bdyp_sufiLinearBoundary defining proclamation
pte_road_clroad_clLinearPrivate road centreline.
pte_route_clroad_clLinearPrivate route centreline.
r_line p_sufiLinearBoundary to close off road/rail polygons at intersections. Boundary does not coincide with cadastral bdy.
r_line20p_sufiLinearBoundary to close off strata road/rail polygons at intersections. Boundary does not coincide with cadastral bdy.
r_legal_bdyp_sufiLinearRoad legality boundary - used internal to road/rail parcel.
r_legal_arcp_sufiLinearRoad legality arc boundary - used internal to road/rail parcel.
r_r_arc p_sufiLinearRoad/Railway Arc boundaries.
r_r_arc02p_sufiLinearMaori partition Road/Railway Arc boundaries. Cloned from r_r_arc
r_r_arc20p_sufiLinearStrata Road/Railway Arc boundaries. Maybe cloned from r_r_arc
r_r_bdy p_sufiLinearRoad/Railway boundaries. Road and/or Railway boundaries derived from survey plans.
r_r_bdy02p_sufiLinearMaori partition Road/Railway boundaries. Road and/or Railway boundaries derived from survey plans. Cloned from r_r_bdy
r_r_bdy20p_sufiLinearStrata Road/Railway boundaries. Road and/or Railway boundaries derived from survey plans. Maybe cloned from r_r_bdy
r_r_hydp_sufiLinearSurveyed stream/river/lake/coastline edges which are also legal road/rail boundaries.
r_r_hyd02p_sufiLinearSurveyed stream/river/lake/coastline edges which are also legal maori partition road/rail boundaries. Cloned from parcel_hyd
rail_segmentrailwayPolygonCentroid feature used for rail polygon formation
rail_seg20railwayPolygonStrata centroid feature used for rail polygon formation
railway_clrailwayLinearRailway centreline
regionregionPolygonRegional Council polygon centroid
region_bdyp_sufiLinearBoundary for Regional Council derived from meshblocks.
road_clroad_clLinearRoad centreline
road_legalroad_legalPointRoad legality information
road_legal08road_legalPointMaintenance road legality information - Not for client supply
road_segmentroad_segmentPolygonCentroid feature used for road polygon formation
road_seg20road_segmentPolygonCentroid feature used for road strata polygon formation
road_interroad_interPolygonCentroid feature used for road intersection polygon formation
road_inter20road_interPolygonCentroid feature used for strata road intersection polygon formation
tataPolygonTerritorial Authority centroid
ta_bdyp_sufiLinearBoundary for Territorial Authority derived from meshblocks.
wardwardPolygonTerritorial Authority Ward centroid
ward_bdyp_sufiLinearBoundary for Territorial Authority Ward derived from meshblocks.
walkway_clroad_clLinearCentreline defining walkways

The relationship between the various features and the networks (or layers) is shown in the following diagram.

Database/Map

Cadastral Layer 100

NetworksSurvey
1000
Partition
1002
Centreline
1005
Road Legality
1006
 h_line
hyd_segment
parcel
parcel_arc
parcel_bdy
parcel_hyd
r_line
r_r_arc
r_r_bdy
r_r_hyd
rail_segment
road_inter
road_segment
m_part_bdy
parcel02
parcel_arc02
parcel_bdy02
parcel_hyd02
r_r_arc02
r_r_bdy02
r_r_hyd02
access_cl
easement_cl
pte_road_cl
pte_route_cl
railway_cl
road_cl
walkway_cl
r_legal_arc
r_legal_bdy
road_legal
NetworksAddress
1007
Survey Maint
1008
EMF
1009
 
 addressparcel1008
emf1008
maint_bdy
road_legal08
emf 

NOTE - The Survey Maint network (1008) is not available for client supply.

District Layer 101

NetworksLand
1011
 land_dist
ld_bdy

Strata Layer 102

NetworksParcel Strata
1020
 parcel20
parcel_arc20
parcel_bdy20
r_line20
r_r_arc20
r_r_bdy20
rail_seg20
road_inter20
road_seg20

Statute Layer 103

NetworksProclamation
1032
 parcel32
proc_bdy

NOTE - The Proclamation network (1032) is not available for client supply.

Stats/Admin Layer 104

NetworksMeshblock
1040
Ward
1043
TA
1044
Region
1045
Constituency
1046
 mesh_bdy
mesh_cad
mesh_other
mesh_topo
meshblock
ward
ward_bdy
ta
ta_bdy
region
region_bdy
constituency
constit_bdy
NetworksGeneral
1047
Maori
1048
No Licence
1049
  
 general
general_bdy
maori
maori_bdy
no_licence
no_lic_bdy
  

Plan Reference Layer 106

NetworksPlan
1060
 plan
plan_prov

3.3. Tables

3.3.1. Primary Tables

The DCDB database schema has 21 user defined primary tables for storing attribute data. Attributes are stored within these tables via user attribute forms associated with certain feature codes, eg. the feature code "road_cl" (road centreline) has the table "road_cl" associated with it.

The user table definitions show the layout of these tables, what columns each table has, what type the column is, the maximum number of characters allowed in each column (size), whether or not a null value is permitted, whether there is an index on the column, if the column contains unique values and the range of feature codes associated with the table.

The emf, land_district and temp_query primary tables are not expanded on in the Data Characteristics manual as they are specific to Land Information NZ internal operations only.

3.3.2. Indirect Tables

Indirect tables contain information not directly associated with a database feature. There are two types of indirect tables - lookup and association. See Appendix 4

The lookup tables are used to resolve data redundancy issues. This means a field need only be entered once but can be accessed via multiple primary tables.

The association tables are used to resolve many to many relationships between primary tables.

There are 5 indirect (2 lookup and 3 association) tables defined within the DCDB database schema - they are:

ROAD_LOOKUP:
Attributes: sufi, created_date, modified_date, road_name, road_type, road_suffix, unofficial flag, asp_location
Description: This lookup table holds entries that would otherwise be replicated in the ADDRESS table, ROAD_CL table and ROAD_SEGMENT table. The only way road names can be entered into the DCDB is via a valid entry in the Authoritative Streets and Places (ASP) database. See Appendix 4.
RD_NAME_SEGMENT:
Attributes: road_lookup sufi and road_segment sufi.
Description: This association table resolves the many to many relationship between the ROAD_LOOKUP table and the ROAD_SEGMENT table. See Appendix 4.
RD_NAME_CL:
Attributes: road_lookup_sufi and road_cl_sufi.
Description: This association table resolves the many to many relationship between the ROAD_CL table and the ROAD_LOOKUP table. See Appendix 4.
ADDRESS_RELATIONS:
Attributes: address_sufi and parcel_sufi.
Description: This association table resolves the many to many relationship between the PARCEL table and the ADDRESS table to allow for multiple addresses. See Appendix 4.
PLAN_LOOKUP:
Attributes: sufi, created_date, modified_date, plan_type, plan_no, plan_suffix, datum, plan_description.
Description: This lookup table holds plan reference entries that would otherwise be replicated in the COVENANT table, PARCEL table and SURV_PLAN table. See Appendix 4.

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