공간정보연구원 PostGIS 강의교재

2014년 7월 23일
공간정보연구원
오픈 소스 GIS 교육
㈜엔지스
윤정환(lenablue12@en-gis.com)
PostGIS
한국어 지부

공간정보연구원 - 오픈 소스 GIS 교육 윤정환 (lenablue12@en-gis.com)
목차
I. PostGIS 개요
I-1. Whati is Spatial Database
I-2. PostGIS Site 둘러보기
I-3. PostGIS를 지원하는 GIS 프로그램
I-4. Open Source Geostack
II. PostGIS 설치 및 환경설정
II-1. OpenGeo Suite 소개
II-2 PostGIS 설치하기
II-3. PostGIS 환경설정
II-4. pgAdmin & Query Tool 사용하기
III. 공간데이터베이스 관리
III-1. 공간 데이터베이스 생성
III-2. 공간 데이터 생성 & 로딩 & 추출
III-3. 래스터 데이터 생성 & 로딩
IV. 공간함수 사용하기
IV-1. PostGIS Reference
IV-2. 실습예제 - I
IV-3. 실습예제 - II
IV-4. Raster Reference
IV-5. Topology
V. 어플리케이션을 이용한 PostGIS 사용하기
V-1. 프로그램 설치하기
V-2. QGIS 이용한 PostGIS 사용하기
V-3. OpenJump 이용한 PostGIS 사용하기
V-4. uDig 이용한 PostGIS 사용하기
V-5. JDBC Driver 이용한 PostGIS 이용하기
V-6. .NET Driver 이용한 PostGIS 이용하기
VI. PostGIS 그밖의 기능
VI-1. Tuning PostgreSQL for Spatial
VI-2. Query Plans
VI-3. 백업 & 복원
VI-4. pgRouting 소개
VI-5. Reference

I. PostGIS 개요
- 일러두기 -
• 본 자료는 모두 Creative Commons License CC-BY-NC을 따릅니다.
• 본 교재에서는 교육의 편의상 Windows 32비트 기반의 프로그램들을 위주로 설명합니다.
• 본 교재에서 사용하는 샘플 데이터 셋은 실제 정보와 다르므로 교육용 이외에는 사용할 수 없습니다.

 PostGIS란 ?
I-1. What is a Spatial DataBase
 PostgreSQL 기반 spatial types, indexes, functions의 3가지 기능을 추가한 공간 데이터베이스
 Spatial databases store/manipulate spatial objects
– data types, indexes, and functions
 Spatial data types
– shapes - point, line, polygon
 Spatial indexing
– efficient processing of spatial operations
 Spatial functions,
– querying of spatial properties and relationships.
http://www.postgis.net/
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 PostGIS Site 둘러보기
I-2. PostGIS Site 둘러보기 - 1
 PostGIS 관련된 Site 둘러보기
http://www.postgis.net/
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http://www.postgresql.org/

 PostGIS Site 둘러보기
I-2. PostGIS Site 둘러보기 - 2
 PostGIS 관련된 Site 둘러보기
http://boundlessgeo.com/
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http://www.pgadmin.org/

 PostGIS를 지원하는 GIS 프로그램
I-3. PostGIS를 지원하는 GIS 프로그램
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Open/Free Closed/Proprietary
•Loading/Extracting
• Shp2Pgsql
• ogr2ogr
• Dxf2PostGIS
•Web-Based
• Mapserver
• GeoServer (Java-based WFS / WMS -server )
• SharpMap SDK - for ASP.NET 2.0
• MapGuide Open Source (using FDO)
•Desktop
• uDig
• QGIS
• mezoGIS
• OpenJUMP
• OpenEV
• SharpMap SDK for Microsoft.NET 2.0
• ZigGIS for ArcGIS/ArcObjects.NET
• GvSIG
• GRASS
•Loading/Extracting
• Safe FME Desktop Translator/Converter
•Web-Based
• Ionic Red Spider (now ERDAS)
• Cadcorp GeognoSIS
• Iwan Mapserver
• MapDotNet Server
• MapGuide Enterprise (using FDO)
• ESRI ArcGIS Server 9.3+
•Desktop
• Cadcorp SIS
• Microimages TNTmips GIS
• ESRI ArcGIS 9.3+
• Manifold
• GeoConcept
• MapInfo (v10)
• AutoCAD Map 3D (using FDO)

 Open Source GeoStack
I-4. Open Source GeoStack
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II. PostGIS 설치 및 환경설정
- 일러두기 -

 OpenGeo Suite 소개
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 OpenGeo Suite

 OpenGeo Suite 설치 - 1
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C:ProgramDataBoundlessOpenGeo

II-2. PostGIS 설치하기
① http://www.postgresql.org/download/에 접속하여 PostgreSQL 최신버전(PostgreSQL 9.3.2)을 내려 받음
② http://download.osgeo.org/postgis/windows/에 접속하여 PostGIS 최신버전(PostGIS 2.1.1)을 내려받음
③ [설치프로그램postgis] 경로로 이동하여 PostgreSQL, PostGIS 최신버전을 설치
– DBMS 설치 : postgresql-9.3.2-1-windows
– Spatial Extension 설치 : postgis-bundle-pg93x32-setup-2.1.1-1
④ PostgreSQL, PostGIS 기본적인 설정에 따라 설치를 완료
⑤ [시작메뉴] – [PostgreSQL 9.3] – [pgAdmin] 을 실행
 PostgreSQL 단독설치 (Application Stack Builder) - 1
PostgreSQL 설치 PostGIS 설치 pgAdmin 실행
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PostgreSQL: http://www.postgresql.org/download/
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Password : postgis
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사용자 컴퓨터의 등록정보를 확인하여 컴퓨터 이름
또는 사용자 이름이 한글일 경우 오류가 발생할 수
있으므로 변경 후 설치 권장합니다

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① http://boundlessgeo.com/에 접속하여 OpenGeo Suite 최신버전을 내려받음
② [설치프로그램postgis] 경로로 이동하여 OpenGeo Suite 3.0.2 버전을 복사
③ OpenGeo Suite 기본적인 설정에 따라 설치를 완료
④ [시작메뉴] – [OpenGeo Suite 3.0.2] – [OpenGeo Suite Dashboard] 를 실행
⑤ OpenGeo Suite Dashboard 화면 우측 상단 [Start] 버튼을 선택
⑥ [Components] – [PostGIS] – [manage] 를 선택하여 pgAdmin을 실행
⑦ Tip : 사용자 컴퓨터의 등록정보를 확인하여 컴퓨터 이름 또는 사용자 이름이 한글일 경우 오류가 발생할 수 있
으므로 변경 후 설치 권장
 OpenGeo Suit 설치
OpenGeo Suite 설치 OpenGeo Suite Dashboard 실행 pgAdmin 실행
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II-3. PostGIS 환경설정
 OpenGeoSuite Dashbord 환결설정
① OpenGeo Suite Dashboard 화면 선택
② Preferences를 선택하고, [PostGIS] 메뉴에 Port 번호 “54321”을 확인
 pgAdmin 환경설정
① [시작메뉴] – [PostgreSQL 9.3] – [pgAdmin] 을 실행
② pgAdmin의 [File] – [Options] 메뉴를 선택
③ [General tab] – [user language] 의 Default를 확인
④ [Preferences tab] – [Font] 선택하여 “돋움, 9”로 변경
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 pgAdmin 사용하기
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메뉴 툴바
객체 브라우저
View

 pgAdmin 사용하기
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도구 설명
pgAdmin 도구에 새로운 서버를 추가합니다.
객체의 정보를 생성, 수정, 갱신, 삭제 후 새로고침 합니다.
테이블 등의 객체의 등록정보를 확인하거나 수정합니다.
선택된 객체와 같은 형태의 새로운 객체를 생성합니다.
선택된 객체를 삭제합니다.
SQL을 실행할 수 있는 Query 도구를 불러옵니다.
선택된 테이블을 편집할 수 있는 테이블 편집기를 불러옵니다.
필터를 적용해서 테이블을 편집할 수 있는 테이블 편집기를 불러옵니다.
Vacuum, Analyze 등 테이블 유지에 필요한 도구를 불러옵니다.

 pgAdmin Server 구성하기
② [File] – [Add Server] & 툴바 아이콘을 선택
③ New Server Registration 화면에 Name, Host, Password를 입력 후 [ok] 선택
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postgis

 Query Tool 사용하기
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① pgAdmin Tool 툴바 아이콘을 선택 Query Tool 실행 – “SELECT version();”
② 샘플데이터 폴더의 postgis_korea_epsg_towgs84.sql을 열기
③ [F5] 선택 Query 실행 시킴, 한국 주요 좌표계 적용
Query 다루기 좌표 등록 시키기

III. 공간데이터베이스 관리
- 일러두기 -

III-1. 공간데이터베이스 생성
② [Databases] 오른쪽 마우스 선택 후 [New Database]를 선택
③ [Name] – nyc 입력
④ [Owner] – postgres 선택, [ok] 선택
⑤ [ ] 선택, Query Tool 실행
⑦ CREATE EXTENSION postgis; 입력, [F5] 실행
⑧ CREATE EXTENSION postgis_topology; 입력, [F5] 실행
⑨ SELECT postgis_full_version(); 입력, [F5] 실행
 GUI를 이용한 공간데이터베이스 생성
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III-2. 공간데이터 생성 & 로딩 & 추출
 공간데이터 로딩 - nyc
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① [시작메뉴] – [PostGIS 2.1 bundle for PostgreSQL 9.3 ] – [PostGIS Shapefile and DBF Loader Exporter] 을 실행
② [PostGIS Connection] – [View connenction details] 선택 후 아래의 내용 입력
- Username : postgres / Password : postgis /Database : nyc
③ [Options] - UTF-8 확인 후 [ok] 선택
④ [Add File] – [02_실습예제02_PostGISdatanyc] 폴더의 Shape 파일 추가
⑤ Import List [SRID] 컬럼 26918 로 변경 입력
⑥ [Import] 선택 Shape 파일 추가

 공간데이터 로딩 - korea
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① [시작메뉴] – [PostGIS 2.1 bundle for PostgreSQL 9.3 ] – [PostGIS Shapefile and DBF Loader Exporter] 을 실행
② [PostGIS Connection ] – [View connenction details] 선택 후 아래의 내용 입력
- Username : postgres / Password : postgis /Database : korea
③ [Options] – encoding CP949 or EUC-KR 변경 입력 후 [ok] 선택
④ [Add File] – [02_실습예제02_PostGISdataseoul] 폴더의 Shape 파일 추가
⑤ Import List [SRID] 컬럼 5174 로 변경 입력
⑥ [Import] 선택 Shape 파일 추가

 공간데이터 추출
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① [시작메뉴] – [PostGIS 2.1 bundle for PostgreSQL 9.3 ] – [pgAdmin III] 을 실행
② OpenGeo Suit Dashboard의 PostGIS [Manage] 선택 실행
③ nyc의 Query Tool을 선택
④ nyc_neighborhoods 테이블을 이용하여 다음 쿼리 문을 작성해 보시기 바랍니다.
- 브루클린에 있는 모든 지역의 이름(name)은 ?
- 브루클린에 있는 모든 지역의 이름에 있는 문자의 수는 ?
- 브루클린에 있는 모든 지역의 이름에 있는 문자의 평균과
표준편차는?
⑤ Function List
- avg(expression)
- char_lengtth(string)
- stddev(string)

 공간데이터 추출
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③ korea의 Query Tool을 선택
④ admin_emd 테이블과 pop2007, pop2008 컬럼을 이용하여 다음 쿼리 문을 작성해 보시기 바랍니다.
- 서울특별시 2007, 2008 각 년도 인구수 총 합은 ?
- 서울특별시 종로구, 서대문구, 강남구 2007, 2008 각년도
인구수의 총 합은?
- 2008년 인구 중 종로구내 각 동의 인구비율은 백분율로
표시 ?
⑤ Function List
- avg(expression)
- count(expression)
- sum(expression)

 레스터 데이터 생성
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③ nyc의 Query Tool을 선택
④ PostGIS 래스터 공간함수를 사용한 래스터 테이블 생성
- CREATE TABLE myrasters(rid serial primary key, rast raster);
- CREATE INDEX myrasters_rast_st_convexhull_idx ON
myrasters USING gist( ST_ConvexHull(rast) );

 레스터 데이터 로딩
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① 윈도우 cmd 화면을 실행 ([시작메뉴] – [실행] – [cmd] 선택)
② PostgreSQL 설치경로 이동
③ raster2pgsql –G 입력 실행
④ 실행 예제
⑤ http://postgis.net/docs/manual-2.1/using_raster_dataman.html#RT_Raster_Loader
⑥ C:OpenGISEdupostgisdataseoul_raster 경로 raster 파일 올리기
Raster2pgsql raster_options_go_here raster_file
someschema.sometable > out.sql

IV. 공간함수 사용하기
- 일러두기 -

 reference
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http://postgis.net/docs/manual-2.1/ http://suite.opengeo.org/opengeo-docs/dataadmin/index.html

 Management Functions (http://postgis.net/docs/manual-2.1/reference.html#Management_Functions)
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 AddGeometryColumn — Adds a geometry column to an existing table of attributes. By default uses type modifier
to define rather than constraints. Pass in false for use_typmod to get old check constraint based behavior
 DropGeometryColumn — Removes a geometry column from a spatial table.
 DropGeometryTable — Drops a table and all its references in geometry_columns.
 PostGIS_Full_Version — Reports full postgis version and build configuration infos.
 PostGIS_GEOS_Version — Returns the version number of the GEOS library.
 PostGIS_LibXML_Version — Returns the version number of the libxml2 library.
 PostGIS_Lib_Build_Date — Returns build date of the PostGIS library.
 PostGIS_Lib_Version — Returns the version number of the PostGIS library.
 PostGIS_PROJ_Version — Returns the version number of the PROJ4 library.
 PostGIS_Scripts_Build_Date — Returns build date of the PostGIS scripts.
 PostGIS_Scripts_Installed — Returns version of the postgis scripts installed in this database.
 PostGIS_Scripts_Released — Returns the version number of the postgis.sql script released with the installed postgis
lib.
 PostGIS_Version — Returns PostGIS version number and compile-time options.
 Populate_Geometry_Columns — Ensures geometry columns are defined with type modifiers or have appropriate
spatial constraints This ensures they will be registered correctly in geometry_columns view. By default will convert all
geometry columns with no type modifier to ones with type modifiers. To get old behavior set use_typmod=false
 UpdateGeometrySRID — Updates the SRID of all features in a geometry column, geometry_columns metadata and
srid. If it was enforced with constraints, the constraints will be updated with new srid constraint. If the old was
enforced by type definition, the type definition will be changed.

 Geometry Constructors (http://postgis.net/docs/manual-2.1/reference.html#Geometry_Constructors)
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 ST_BdPolyFromText — Construct a Polygon given an arbitrary collection of closed linestrings as a MultiLineString
Well-Known text representation.
 ST_BdMPolyFromText — Construct a MultiPolygon given an arbitrary collection of closed linestrings as a
MultiLineString text representation Well-Known text representation.
 ST_Box2dFromGeoHash — Return a BOX2D from a GeoHash string.
 ST_GeogFromText — Return a specified geography value from Well-Known Text representation or extended (WKT).
 ST_GeographyFromText — Return a specified geography value from Well-Known Text representation or extended
(WKT).
 ST_GeogFromWKB — Creates a geography instance from a Well-Known Binary geometry representation (WKB) or
extended Well Known Binary (EWKB).
 ST_GeomCollFromText — Makes a collection Geometry from collection WKT with the given SRID. If SRID is not give,
it defaults to 0.
 ST_GeomFromEWKB — Return a specified ST_Geometry value from Extended Well-Known Binary representation
(EWKB).
 ST_GeomFromEWKT — Return a specified ST_Geometry value from Extended Well-Known Text representation
(EWKT).
 ST_GeometryFromText — Return a specified ST_Geometry value from Well-Known Text representation (WKT). This is
an alias name for ST_GeomFromText
 ST_GeomFromGeoHash — Return a geometry from a GeoHash string.
 ST_GeomFromGML — Takes as input GML representation of geometry and outputs a PostGIS geometry object

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 ST_GeomFromGeoJSON — Takes as input a geojson representation of a geometry and outputs a PostGIS geometry
object
 ST_GeomFromKML — Takes as input KML representation of geometry and outputs a PostGIS geometry object
 ST_GMLToSQL — Return a specified ST_Geometry value from GML representation. This is an alias name for
ST_GeomFromGML
 ST_GeomFromText — Return a specified ST_Geometry value from Well-Known Text representation (WKT).
 ST_GeomFromWKB — Creates a geometry instance from a Well-Known Binary geometry representation (WKB) and
optional SRID.
 ST_LineFromMultiPoint — Creates a LineString from a MultiPoint geometry.
 ST_LineFromText — Makes a Geometry from WKT representation with the given SRID. If SRID is not given, it defaults
to 0.
 ST_LineFromWKB — Makes a LINESTRING from WKB with the given SRID
 ST_LinestringFromWKB — Makes a geometry from WKB with the given SRID.
 ST_MakeBox2D — Creates a BOX2D defined by the given point geometries.
 ST_3DMakeBox — Creates a BOX3D defined by the given 3d point geometries.
 ST_MakeLine — Creates a Linestring from point or line geometries.
 ST_MakeEnvelope — Creates a rectangular Polygon formed from the given minimums and maximums. Input values
must be in SRS specified by the SRID.
 ST_MakePolygon — Creates a Polygon formed by the given shell. Input geometries must be closed LINESTRINGS.
 ST_MakePoint — Creates a 2D,3DZ or 4D point geometry.

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 ST_MakePointM — Creates a point geometry with an x y and m coordinate.
 ST_MLineFromText — Return a specified ST_MultiLineString value from WKT representation.
 ST_MPointFromText — Makes a Geometry from WKT with the given SRID. If SRID is not give, it defaults to 0.
 ST_MPolyFromText — Makes a MultiPolygon Geometry from WKT with the given SRID. If SRID is not give, it defaults
to 0.
 ST_Point — Returns an ST_Point with the given coordinate values. OGC alias for ST_MakePoint.
 ST_PointFromGeoHash — Return a point from a GeoHash string.
 ST_PointFromText — Makes a point Geometry from WKT with the given SRID. If SRID is not given, it defaults to
unknown.
 ST_PointFromWKB — Makes a geometry from WKB with the given SRID
 ST_Polygon — Returns a polygon built from the specified linestring and SRID.
 ST_PolygonFromText — Makes a Geometry from WKT with the given SRID. If SRID is not give, it defaults to 0.
 ST_WKBToSQL — Return a specified ST_Geometry value from Well-Known Binary representation (WKB). This is an
alias name for ST_GeomFromWKB that takes no srid
 ST_WKTToSQL — Return a specified ST_Geometry value from Well-Known Text representation (WKT). This is an alias
name for ST_GeomFromText

 Geometry Accessors (http://postgis.net/docs/manual-2.1/reference.html#Geometry_Accessors)
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 GeometryType — Returns the type of the geometry as a string. Eg: 'LINESTRING', 'POLYGON', 'MULTIPOINT', etc.
 ST_Boundary — Returns the closure of the combinatorial boundary of this Geometry.
 ST_CoordDim — Return the coordinate dimension of the ST_Geometry value.
 ST_Dimension — The inherent dimension of this Geometry object, which must be less than or equal to the
coordinate dimension.
 ST_EndPoint — Returns the last point of a LINESTRING geometry as a POINT.
 ST_Envelope — Returns a geometry representing the double precision (float8) bounding box of the supplied
geometry.
 ST_ExteriorRing — Returns a line string representing the exterior ring of the POLYGON geometry. Return NULL if the
geometry is not a polygon. Will not work with MULTIPOLYGON
 ST_GeometryN — Return the 1-based Nth geometry if the geometry is a GEOMETRYCOLLECTION, (MULTI)POINT,
(MULTI)LINESTRING, MULTICURVE or (MULTI)POLYGON, POLYHEDRALSURFACE Otherwise, return NULL.
 ST_GeometryType — Return the geometry type of the ST_Geometry value.
 ST_InteriorRingN — Return the Nth interior linestring ring of the polygon geometry. Return NULL if the geometry is
not a polygon or the given N is out of range.
 ST_IsClosed — Returns TRUE if the LINESTRING's start and end points are coincident. For Polyhedral surface is
closed (volumetric).
 ST_IsCollection — Returns TRUE if the argument is a collection (MULTI*, GEOMETRYCOLLECTION, ...)
 ST_IsEmpty — Returns true if this Geometry is an empty geometrycollection, polygon, point etc.
 ST_IsRing — Returns TRUE if this LINESTRING is both closed and simple.
 ST_IsSimple — Returns (TRUE) if this Geometry has no anomalous geometric points, such as self intersection or self
tangency.

36
 ST_IsValid — Returns true if the ST_Geometry is well formed.
 ST_IsValidReason — Returns text stating if a geometry is valid or not and if not valid, a reason why.
 ST_IsValidDetail — Returns a valid_detail (valid,reason,location) row stating if a geometry is valid or not and if not
valid, a reason why and a location where.
 ST_M — Return the M coordinate of the point, or NULL if not available. Input must be a point.
 ST_NDims — Returns coordinate dimension of the geometry as a small int. Values are: 2,3 or 4.
 ST_NPoints — Return the number of points (vertexes) in a geometry.
 ST_NRings — If the geometry is a polygon or multi-polygon returns the number of rings.
 ST_NumGeometries — If geometry is a GEOMETRYCOLLECTION (or MULTI*) return the number of geometries, for
single geometries will return 1, otherwise return NULL.
 ST_NumInteriorRings — Return the number of interior rings of the a polygon in the geometry. This will work with
POLYGON and return NULL for a MULTIPOLYGON type or any other type
 ST_NumInteriorRing — Return the number of interior rings of the first polygon in the geometry. Synonym to
ST_NumInteriorRings.
 ST_NumPatches — Return the number of faces on a Polyhedral Surface. Will return null for non-polyhedral
geometries.
 ST_NumPoints — Return the number of points in an ST_LineString or ST_CircularString value.
 ST_PatchN — Return the 1-based Nth geometry (face) if the geometry is a POLYHEDRALSURFACE,
POLYHEDRALSURFACEM. Otherwise, return NULL.
 ST_PointN — Return the Nth point in the first linestring or circular linestring in the geometry. Return NULL if there is
no linestring in the geometry.

37
 ST_SRID — Returns the spatial reference identifier for the ST_Geometry as defined in spatial_ref_sys table.
 ST_StartPoint — Returns the first point of a LINESTRING geometry as a POINT.
 ST_Summary — Returns a text summary of the contents of the geometry.
 ST_X — Return the X coordinate of the point, or NULL if not available. Input must be a point.
 ST_XMax — Returns X maxima of a bounding box 2d or 3d or a geometry.
 ST_XMin — Returns X minima of a bounding box 2d or 3d or a geometry.
 ST_Y — Return the Y coordinate of the point, or NULL if not available. Input must be a point.
 ST_YMax — Returns Y maxima of a bounding box 2d or 3d or a geometry.
 ST_YMin — Returns Y minima of a bounding box 2d or 3d or a geometry.
 ST_Z — Return the Z coordinate of the point, or NULL if not available. Input must be a point.
 ST_ZMax — Returns Z minima of a bounding box 2d or 3d or a geometry.
 ST_Zmflag — Returns ZM (dimension semantic) flag of the geometries as a small int. Values are: 0=2d, 1=3dm,
2=3dz, 3=4d.
 ST_ZMin — Returns Z minima of a bounding box 2d or 3d or a geometry.

 Geometry Editors (http://postgis.net/docs/manual-2.1/reference.html#Geometry_Editors)
38
 ST_AddPoint — Adds a point to a LineString before point <position> (0-based index).
 ST_Affine — Applies a 3d affine transformation to the geometry to do things like translate, rotate, scale in one step.
 ST_Force2D — Forces the geometries into a "2-dimensional mode" so that all output representations will only have
the X and Y coordinates.
 ST_Force3D — Forces the geometries into XYZ mode. This is an alias for ST_Force3DZ.
 ST_Force3DZ — Forces the geometries into XYZ mode. This is a synonym for ST_Force3D.
 ST_Force3DM — Forces the geometries into XYM mode.
 ST_Force4D — Forces the geometries into XYZM mode.
 ST_ForceCollection — Converts the geometry into a GEOMETRYCOLLECTION.
 ST_ForceSFS — Forces the geometries to use SFS 1.1 geometry types only.
 ST_ForceRHR — Forces the orientation of the vertices in a polygon to follow the Right-Hand-Rule.
 ST_LineMerge — Returns a (set of) LineString(s) formed by sewing together a MULTILINESTRING.
 ST_CollectionExtract — Given a (multi)geometry, returns a (multi)geometry consisting only of elements of the
specified type.
 ST_CollectionHomogenize — Given a geometry collection, returns the "simplest" representation of the contents.
 ST_Multi — Returns the geometry as a MULTI* geometry. If the geometry is already a MULTI*, it is returned
unchanged.
 ST_RemovePoint — Removes point from a linestring. Offset is 0-based.
 ST_Reverse — Returns the geometry with vertex order reversed.
 ST_Rotate — Rotate a geometry rotRadians counter-clockwise about an origin.

 Geometry Editors (http://postgis.net/docs/manual-2.1/reference.html#Geometry_Editors)
39
 ST_RotateX — Rotate a geometry rotRadians about the X axis.
 ST_RotateY — Rotate a geometry rotRadians about the Y axis.
 ST_RotateZ — Rotate a geometry rotRadians about the Z axis.
 ST_Scale — Scales the geometry to a new size by multiplying the ordinates with the parameters. Ie: ST_Scale(geom,
Xfactor, Yfactor, Zfactor).
 ST_Segmentize — Return a modified geometry/geography having no segment longer than the given distance.
Distance computation is performed in 2d only. For geometry, length units are in units of spatial reference. For
geography, units are in meters.
 ST_SetPoint — Replace point N of linestring with given point. Index is 0-based.
 ST_SetSRID — Sets the SRID on a geometry to a particular integer value.
 ST_SnapToGrid — Snap all points of the input geometry to a regular grid.
 ST_Snap — Snap segments and vertices of input geometry to vertices of a reference geometry.
 ST_Transform — Returns a new geometry with its coordinates transformed to the SRID referenced by the integer
parameter.
 ST_Translate — Translates the geometry to a new location using the numeric parameters as offsets. Ie:
ST_Translate(geom, X, Y) or ST_Translate(geom, X, Y,Z).
 ST_TransScale — Translates the geometry using the deltaX and deltaY args, then scales it using the XFactor, YFactor
args, working in 2D only.

 Geometry Outputs (http://postgis.net/docs/manual-2.1/reference.html#Geometry_Outputs)
40
 ST_AsBinary — Return the Well-Known Binary (WKB) representation of the geometry/geography without SRID meta
data.
 ST_AsEWKB — Return the Well-Known Binary (WKB) representation of the geometry with SRID meta data.
 ST_AsEWKT — Return the Well-Known Text (WKT) representation of the geometry with SRID meta data.
 ST_AsGeoJSON — Return the geometry as a GeoJSON element.
 ST_AsGML — Return the geometry as a GML version 2 or 3 element.
 ST_AsHEXEWKB — Returns a Geometry in HEXEWKB format (as text) using either little-endian (NDR) or big-endian
(XDR) encoding.
 ST_AsKML — Return the geometry as a KML element. Several variants. Default version=2, default precision=15
 ST_AsSVG — Returns a Geometry in SVG path data given a geometry or geography object.
 ST_AsX3D — Returns a Geometry in X3D xml node element format: ISO-IEC-19776-1.2-X3DEncodings-XML
 ST_GeoHash — Return a GeoHash representation of the geometry.
 ST_AsText — Return the Well-Known Text (WKT) representation of the geometry/geography without SRID metadata.
 ST_AsLatLonText — Return the Degrees, Minutes, Seconds representation of the given point.

 Operators (http://postgis.net/docs/manual-2.1/reference.html#Operators)
41
 && — Returns TRUE if A's 2D bounding box intersects B's 2D bounding box.
 &&& — Returns TRUE if A's 3D bounding box intersects B's 3D bounding box.
 &< — Returns TRUE if A's bounding box overlaps or is to the left of B's.
 &<| — Returns TRUE if A's bounding box overlaps or is below B's.
 &> — Returns TRUE if A' bounding box overlaps or is to the right of B's.
 << — Returns TRUE if A's bounding box is strictly to the left of B's.
 <<| — Returns TRUE if A's bounding box is strictly below B's.
 = — Returns TRUE if A's bounding box is the same as B's. Uses double precision bounding box.
 >> — Returns TRUE if A's bounding box is strictly to the right of B's.
 @ — Returns TRUE if A's bounding box is contained by B's.
 |&> — Returns TRUE if A's bounding box overlaps or is above B's.
 |>> — Returns TRUE if A's bounding box is strictly above B's.
 ~ — Returns TRUE if A's bounding box contains B's.
 ~= — Returns TRUE if A's bounding box is the same as B's.
 <-> — Returns the distance between two points. For point / point checks it uses floating point accuracy (as opposed
to the double precision accuracy of the underlying point geometry). For other geometry types the distance between
the floating point bounding box centroids is returned. Useful for doing distance ordering and nearest neighbor limits
using KNN gist functionality.
 <#> — Returns the distance between bounding box of 2 geometries. For point / point checks it's almost the same
as distance (though may be different since the bounding box is at floating point accuracy and geometries are
double precision). Useful for doing distance ordering and nearest neighbor limits using KNN gist functionality.

 Spatial Relationships and Measurements (http://postgis.net/docs/manual-2.1/reference.html#Spatial_Relationships_Measurements)
42
 ST_3DClosestPoint — Returns the 3-dimensional point on g1 that is closest to g2. This is the first point of the 3D
shortest line.
 ST_3DDistance — For geometry type Returns the 3-dimensional cartesian minimum distance (based on spatial ref)
between two geometries in projected units.
 ST_3DDWithin — For 3d (z) geometry type Returns true if two geometries 3d distance is within number of units.
 ST_3DDFullyWithin — Returns true if all of the 3D geometries are within the specified distance of one another.
 ST_3DIntersects — Returns TRUE if the Geometries "spatially intersect" in 3d - only for points and linestrings
 ST_3DLongestLine — Returns the 3-dimensional longest line between two geometries
 ST_3DMaxDistance — For geometry type Returns the 3-dimensional cartesian maximum distance (based on spatial
ref) between two geometries in projected units.
 ST_3DShortestLine — Returns the 3-dimensional shortest line between two geometries
 ST_Area — Returns the area of the surface if it is a polygon or multi-polygon. For "geometry" type area is in SRID
units. For "geography" area is in square meters.
 ST_Azimuth — Returns the north-based azimuth as the angle in radians measured clockwise from the vertical on
pointA to pointB.
 ST_Centroid — Returns the geometric center of a geometry.
 ST_ClosestPoint — Returns the 2-dimensional point on g1 that is closest to g2. This is the first point of the shortest
line.
 ST_Contains — Returns true if and only if no points of B lie in the exterior of A, and at least one point of the
interior of B lies in the interior of A.
 ST_ContainsProperly — Returns true if B intersects the interior of A but not the boundary (or exterior). A does not
contain properly itself, but does contain itself.

43
 ST_Covers — Returns 1 (TRUE) if no point in Geometry B is outside Geometry A
 ST_CoveredBy — Returns 1 (TRUE) if no point in Geometry/Geography A is outside Geometry/Geography B
 ST_Crosses — Returns TRUE if the supplied geometries have some, but not all, interior points in common.
 ST_LineCrossingDirection — Given 2 linestrings, returns a number between -3 and 3 denoting what kind of crossing
behavior. 0 is no crossing.
 ST_Disjoint — Returns TRUE if the Geometries do not "spatially intersect" - if they do not share any space together.
 ST_Distance — For geometry type Returns the 2-dimensional cartesian minimum distance (based on spatial ref)
between two geometries in projected units. For geography type defaults to return spheroidal minimum distance
between two geographies in meters.
 ST_HausdorffDistance — Returns the Hausdorff distance between two geometries. Basically a measure of how similar
or dissimilar 2 geometries are. Units are in the units of the spatial reference system of the geometries.
 ST_MaxDistance — Returns the 2-dimensional largest distance between two geometries in projected units.
 ST_Distance_Sphere — Returns minimum distance in meters between two lon/lat geometries. Uses a spherical earth
and radius of 6370986 meters. Faster than ST_Distance_Spheroid ST_Distance_Spheroid, but less accurate. PostGIS
versions prior to 1.5 only implemented for points.
 ST_Distance_Spheroid — Returns the minimum distance between two lon/lat geometries given a particular spheroid.
PostGIS versions prior to 1.5 only support points.
 ST_DFullyWithin — Returns true if all of the geometries are within the specified distance of one another
 ST_DWithin — Returns true if the geometries are within the specified distance of one another. For geometry units
are in those of spatial reference and For geography units are in meters and measurement is defaulted to
use_spheroid=true (measure around spheroid), for faster check, use_spheroid=false to measure along sphere.

44
 ST_Equals — Returns true if the given geometries represent the same geometry. Directionality is ignored.
 ST_HasArc — Returns true if a geometry or geometry collection contains a circular string
 ST_Intersects — Returns TRUE if the Geometries/Geography "spatially intersect in 2D" - (share any portion of space)
and FALSE if they don't (they are Disjoint). For geography -- tolerance is 0.00001 meters (so any points that close are
considered to intersect)
 ST_Length — Returns the 2d length of the geometry if it is a linestring or multilinestring. geometry are in units of
spatial reference and geography are in meters (default spheroid)
 ST_Length2D — Returns the 2-dimensional length of the geometry if it is a linestring or multi-linestring. This is an
alias for ST_Length
 ST_3DLength — Returns the 3-dimensional or 2-dimensional length of the geometry if it is a linestring or multi-
linestring.
 ST_Length_Spheroid — Calculates the 2D or 3D length of a linestring/multilinestring on an ellipsoid. This is useful if
the coordinates of the geometry are in longitude/latitude and a length is desired without reprojection.
 ST_Length2D_Spheroid — Calculates the 2D length of a linestring/multilinestring on an ellipsoid. This is useful if the
coordinates of the geometry are in longitude/latitude and a length is desired without reprojection.
 ST_3DLength_Spheroid — Calculates the length of a geometry on an ellipsoid, taking the elevation into account. This
is just an alias for ST_Length_Spheroid.
 ST_LongestLine — Returns the 2-dimensional longest line points of two geometries. The function will only return the
first longest line if more than one, that the function finds. The line returned will always start in g1 and end in g2.
The length of the line this function returns will always be the same as st_maxdistance returns for g1 and g2.
 ST_OrderingEquals — Returns true if the given geometries represent the same geometry and points are in the same
directional order.

45
 ST_Overlaps — Returns TRUE if the Geometries share space, are of the same dimension, but are not completely
contained by each other.
 ST_Perimeter — Return the length measurement of the boundary of an ST_Surface or ST_MultiSurface geometry or
geography. (Polygon, Multipolygon). geometry measurement is in units of spatial reference and geography is in
meters.
 ST_Perimeter2D — Returns the 2-dimensional perimeter of the geometry, if it is a polygon or multi-polygon. This is
currently an alias for ST_Perimeter.
 ST_3DPerimeter — Returns the 3-dimensional perimeter of the geometry, if it is a polygon or multi-polygon.
 ST_PointOnSurface — Returns a POINT guaranteed to lie on the surface.
 ST_Project — Returns a POINT projected from a start point using a distance in meters and bearing (azimuth) in
radians.
 ST_Relate — Returns true if this Geometry is spatially related to anotherGeometry, by testing for intersections
between the Interior, Boundary and Exterior of the two geometries as specified by the values in the
intersectionMatrixPattern. If no intersectionMatrixPattern is passed in, then returns the maximum
intersectionMatrixPattern that relates the 2 geometries.
 ST_RelateMatch — Returns true if intersectionMattrixPattern1 implies intersectionMatrixPattern2
 ST_ShortestLine — Returns the 2-dimensional shortest line between two geometries
 ST_Touches — Returns TRUE if the geometries have at least one point in common, but their interiors do not
intersect.
 ST_Within — Returns true if the geometry A is completely inside geometry B

 SFCGAL Functions (http://postgis.net/docs/manual-2.1/reference.html#reference_sfcgal)
46
 postgis_sfcgal_version — Returns the version of SFCGAL in use
 ST_Extrude — Extrude a surface to a related volume
 ST_StraightSkeleton — Compute a straight skeleton from a geometry
 ST_Orientation — Determine surface orientation
 ST_ForceLHR — Force LHR orientation
 ST_MinkowskiSum — Perform Minkowski sum
 ST_3DIntersection — Perform 3D intersection
 ST_3DArea — Computes area of 3D geometries
 ST_Tesselate — Perform surface Tesselation

 Geometry Processing (http://postgis.net/docs/manual-2.1/reference.html#Geometry_Processing)
47
 ST_Buffer — (T) For geometry: Returns a geometry that represents all points whose distance from this Geometry is
less than or equal to distance. Calculations are in the Spatial Reference System of this Geometry. For geography:
Uses a planar transform wrapper. Introduced in 1.5 support for different end cap and mitre settings to control shape.
buffer_style options: quad_segs=#,endcap=round|flat|square,join=round|mitre|bevel,mitre_limit=#.#
 ST_BuildArea — Creates an areal geometry formed by the constituent linework of given geometry
 ST_Collect — Return a specified ST_Geometry value from a collection of other geometries.
 ST_ConcaveHull — The concave hull of a geometry represents a possibly concave geometry that encloses all
geometries within the set. You can think of it as shrink wrapping.
 ST_ConvexHull — The convex hull of a geometry represents the minimum convex geometry that encloses all
geometries within the set.
 ST_CurveToLine — Converts a CIRCULARSTRING/CURVEDPOLYGON to a LINESTRING/POLYGON
 ST_DelaunayTriangles — Return a Delaunay triangulation around the given input points.
 ST_Difference — Returns a geometry that represents that part of geometry A that does not intersect with geometry
B.
 ST_Dump — Returns a set of geometry_dump (geom,path) rows, that make up a geometry g1.
 ST_DumpPoints — Returns a set of geometry_dump (geom,path) rows of all points that make up a geometry.
 ST_DumpRings — Returns a set of geometry_dump rows, representing the exterior and interior rings of a polygon.
 ST_FlipCoordinates — Returns a version of the given geometry with X and Y axis flipped. Useful for people who have
built latitude/longitude features and need to fix them.
 ST_Intersection — (T) Returns a geometry that represents the shared portion of geomA and geomB. The geography
implementation does a transform to geometry to do the intersection and then transform back to WGS84.

49
 ST_LineToCurve — Converts a LINESTRING/POLYGON to a CIRCULARSTRING, CURVED POLYGON
 ST_MakeValid — Attempts to make an invalid geometry valid without losing vertices.
 ST_MemUnion — Same as ST_Union, only memory-friendly (uses less memory and more processor time).
 ST_MinimumBoundingCircle — Returns the smallest circle polygon that can fully contain a geometry. Default uses
48 segments per quarter circle.
 ST_Polygonize — Aggregate. Creates a GeometryCollection containing possible polygons formed from the
constituent linework of a set of geometries.
 ST_Node — Node a set of linestrings.
 ST_OffsetCurve — Return an offset line at a given distance and side from an input line. Useful for computing parallel
lines about a center line
 ST_RemoveRepeatedPoints — Returns a version of the given geometry with duplicated points removed.
 ST_SharedPaths — Returns a collection containing paths shared by the two input linestrings/multilinestrings.
 ST_Shift_Longitude — Reads every point/vertex in every component of every feature in a geometry, and if the
longitude coordinate is <0, adds 360 to it. The result would be a 0-360 version of the data to be plotted in a 180
centric map
 ST_Simplify — Returns a "simplified" version of the given geometry using the Douglas-Peucker algorithm.
 ST_SimplifyPreserveTopology — Returns a "simplified" version of the given geometry using the Douglas-Peucker
algorithm. Will avoid creating derived geometries (polygons in particular) that are invalid.
 ST_Split — Returns a collection of geometries resulting by splitting a geometry.
 ST_SymDifference — Returns a geometry that represents the portions of A and B that do not intersect. It is called a
symmetric difference because ST_SymDifference(A,B) = ST_SymDifference(B,A).

50
 ST_Union — Returns a geometry that represents the point set union of the Geometries.
 ST_UnaryUnion — Like ST_Union, but working at the geometry component level.

 Linear Referencing (http://postgis.net/docs/manual-2.1/reference.html#Linear_Referencing)
51
 ST_LineInterpolatePoint — Returns a point interpolated along a line. Second argument is a float8 between 0 and 1
representing fraction of total length of linestring the point has to be located.
 ST_LineLocatePoint — Returns a float between 0 and 1 representing the location of the closest point on LineString to
the given Point, as a fraction of total 2d line length.
 ST_LineSubstring — Return a linestring being a substring of the input one starting and ending at the given fractions
of total 2d length. Second and third arguments are float8 values between 0 and 1.
 ST_LocateAlong — Return a derived geometry collection value with elements that match the specified measure.
Polygonal elements are not supported.
 ST_LocateBetween — Return a derived geometry collection value with elements that match the specified range of
measures inclusively. Polygonal elements are not supported.
 ST_LocateBetweenElevations — Return a derived geometry (collection) value with elements that intersect the
specified range of elevations inclusively. Only 3D, 4D LINESTRINGS and MULTILINESTRINGS are supported.
 ST_InterpolatePoint — Return the value of the measure dimension of a geometry at the point closed to the provided
point.
 ST_AddMeasure — Return a derived geometry with measure elements linearly interpolated between the start and
end points. If the geometry has no measure dimension, one is added. If the geometry has a measure dimension, it is
over-written with new values. Only LINESTRINGS and MULTILINESTRINGS are supported.

 Long Transactions Support (http://postgis.net/docs/manual-2.1/reference.html#Long_Transactions_Support)
52
 AddAuth — Add an authorization token to be used in current transaction.
 CheckAuth — Creates trigger on a table to prevent/allow updates and deletes of rows based on authorization token.
 DisableLongTransactions — Disable long transaction support. This function removes the long transaction support
metadata tables, and drops all triggers attached to lock-checked tables.
 EnableLongTransactions — Enable long transaction support. This function creates the required metadata tables,
needs to be called once before using the other functions in this section. Calling it twice is harmless.
 LockRow — Set lock/authorization for specific row in table
 UnlockRows — Remove all locks held by specified authorization id. Returns the number of locks released.
 This module and associated pl/pgsql functions have been implemented to provide long locking support required by
Web Feature Service specification.

 Miscellaneous Functions (http://postgis.net/docs/manual-2.1/reference.html#Miscellaneous_Functions)
53
 ST_Accum — Aggregate. Constructs an array of geometries.
 Box2D — Returns a BOX2D representing the maximum extents of the geometry.
 Box3D — Returns a BOX3D representing the maximum extents of the geometry.
 ST_EstimatedExtent — Return the 'estimated' extent of the given spatial table. The estimated is taken from the
geometry column's statistics. The current schema will be used if not specified.
 ST_Expand — Returns bounding box expanded in all directions from the bounding box of the input geometry. Uses
double-precision
 ST_Extent — an aggregate function that returns the bounding box that bounds rows of geometries.
 ST_3DExtent — an aggregate function that returns the box3D bounding box that bounds rows of geometries.
 Find_SRID — The syntax is find_srid(a_db_schema, a_table, a_column) and the function returns the integer SRID of
the specified column by searching through the GEOMETRY_COLUMNS table.
 ST_Mem_Size — Returns the amount of space (in bytes) the geometry takes.
 ST_Point_Inside_Circle — Is the point geometry insert circle defined by center_x, center_y, radius

 Exceptional Functions (http://postgis.net/docs/manual-2.1/reference.html#Exceptional_Functions)
54
 PostGIS_AddBBox — Add bounding box to the geometry.
 PostGIS_DropBBox — Drop the bounding box cache from the geometry.
 PostGIS_HasBBox — Returns TRUE if the bbox of this geometry is cached, FALSE otherwise.

IV-2. 실습예제 -Ⅰ
- 일러두기 -

IV-2-1. 실습예제 데이터셋 보기
 실습예제 데이터셋 보기
55
Shapefile 레이어명 유형 SRID 비고
admin_emd 읍면동경계 MultiPolygon 5174
admin_sgg 시군구경계 MultiPolygon 5174
admin_sid 시도경계 MultiPolygon 5174
river 실폭하천 MultiPolygon 5174
road_link2 도로 MultiLinestring 5174
firestation 소방서 Point 5174
healthcenter 보건소 Point 5174
policestation 경찰서 Point 5174
stores 대형마트 Point 5174
wardoffice 시군구청 Point 5174
subway 지하철노선 MultiLinestring 5174
Subway_station 지하철역 Point 5174

IV-2-2. 레이어 확인
 레이어 확인
56

IV-2-3. PostGIS Documentation
 PostGIS Documention
57

IV-2-4. 테이블 관리
 공간테이블 생성하기
58
1. cityhall 이라는 공간 테이블을 생성하고, 다음의 정보를 입력하시오.
 X=197977.3885 , Y=451601.1444, city_name =서울
 Function
 AddGeometryColumn( <schema_name>, <table_name>, <column_name>, <srid>, <type>,
<dimension> )
 AddGeometryColumn( <table_name>, <column_name>, <srid>, <type>, <dimension> )
 http://postgis.net/docs/manual-
2.0/using_postgis_dbmanagement.html#OpenGISWKBWKT

 공간인덱싱 생성하기
59
2. 앞 페이지에서 생성한 cityhall 테이블에 공간인덱싱을 생성하시오.
 SQL
 CREATE INDEX [indexname] ON [tablename] USING GIST ( [geometryfield] );
 http://postgis.org/docs/ch04.html#id2628148

 공간테이블 삭제하기
60
3. 앞에서 생성한 cityhall 테이블을 삭제하시오.
 일반적인 과정
 Remove refs from geometry_columns table
 Remove table
 Function
 DropGeometryTable(varchar table_name);
 DropGeometryTable(varchar schema_name, varchar table_name);
 DropGeometryTable(varchar catalog_name, varchar schema_name, varchar table_name);

 공간 뷰(View) 생성 후 등록하기
61
4. 읍면동 행정경계(admin_emd)를 이용하여 종로구에 해당하는 읍면동의 중심점을
admin_emd_point View로 등록하시오.
 Function
 CREATE OR REPLACE VIEW, DROP VIEW
 ST_Centroid(geometry g1)
 Populate_Geometry_Columns()

 SQL을 이용하여 공간테이블 생성 후 등록하기
62
5. 시군구 행정경계(admin_sgg)를 이용하여 종로구에 해당하는 시군구 폴리곤과
Intersects되는 도로(road_link2)를 Clip하여 새로운 테이블로 생성하시오.

IV-2-5. 공간함수
 Measurement
63
6. 서울특별시 중구의 행정경계(admin_sgg) 면적은 얼마인가? 단위는 ㎢로 표현
하시오.
7. 도로 레이어(road_link2) 중 6차선(lanes) 이상의 도로의 길이는 얼마인가? 단.
㎞로 표현하시오.
8. 서울시의 읍면동(admin_emd) 중 면적이 가장 큰 상위 10개를 선택하여 읍면동
이름 및 면적값을 조회하시오.
9. 강(river) 레이어 중 hole을 가진 강은?

공간정보연구원 - 오픈 소스 GIS 교육 윤정환 (lenablue12@en-gis.com)64
 Proximity & Distance
10. 좌표 X = 197215 Y = 447711 지점에서 1KM 반경 내에 있는 대형매장
(stores)은 무엇인가?
 Function
 ST_Distance
 Function
 ST_Dwithin
 Function
 ST_Buffer, ST_Intersects

 Spatial Join
65
13. 한강(river, river_cd = '1')과 인접한 서울시의 구(admin_sgg)는 무엇인가?
14. 영등포구(admin_sgg)에 속한 대형매장(stores)은 무엇인가?
15. 소방서(firestation)에서 500미터 반경 내의 도로 중 가장 가까운 도로
(road_link2)와 거리를 계산하시오.

 Overlay
66
16. 서울시 구별(admin_sgg) 6차선 이상 도로(road_link2, lanes)의 길이를 구하시
오.
17. 서울특별시 중구의 중심점은 어디인가? 단, 경위도로 표시하시오.
 Projection

IV-3. 실습예제 -Ⅱ
- 일러두기 -

IV-3-1. Geometry
 Geometry
67
① nyc의 Query Tool 실행
CREATE TABLE geometries (name varchar, geom geometry);
INSERT INTO geometries VALUES
('Point', 'POINT(0 0)'),
('Linestring', 'LINESTRING(0 0, 1 1, 2 1, 2 2)'),
('Polygon', 'POLYGON((0 0, 1 0, 1 1, 0 1, 0 0))'),
('PolygonWithHole', 'POLYGON((0 0, 10 0, 10 10, 0 10, 0 0),(1 1, 1 2, 2 2, 2 1, 1 1))'),
('Collection', 'GEOMETRYCOLLECTION(POINT(2 0),POLYGON((0 0, 1 0, 1 1, 0 1, 0 0)))');
SELECT name, ST_AsText(geom) FROM geometries;
② Spatial Type
SELECT name, ST_GeometryType(geom), ST_NDims(geom),
ST_SRID(geom) FROM geometries;

IV-3-1. Geometry
 Geometry
68
③ Spatial Type
SELECT name, ST_GeometryType(geom), ST_NDims(geom), ST_SRID(geom) FROM geometries;
④ Point
SELECT ST_AsText(geom) FROM geometries WHERE name = 'Point';
SELECT ST_X(geom), ST_Y(geom) FROM geometries WHERE name = 'Point';
SELECT name, ST_AsText(geom) FROM nyc_subway_stations LIMIT 1;
⑤ Linestrings
SELECT ST_AsText(geom) FROM geometries WHERE name = 'Linestring';
SELECT ST_Length(geom) FROM geometries WHERE name = 'Linestring';

IV-3-1. Geometry
 Geometry
69
⑥ Polygons
SELECT ST_AsText(geom) FROM geometries WHERE name LIKE 'Polygon%';
SELECT name, ST_Area(geom) FROM geometries WHERE name LIKE 'Polygon%
⑦ Collections – MultiPoint, MultiLineString, MultiPolygon, GeometryCollection
SELECT name, ST_AsText(geom) FROM geometries WHERE name = 'Collection';
⑧ Geometry Input and Output
SELECT encode( ST_AsBinary(ST_GeometryFromText('LINESTRING(0 0 0,1 0 0,1 1 2)')), 'hex');
SELECT ST_AsEWKT(ST_GeometryFromText('LINESTRING(0 0 0,1 0 0,1 1 2)'));
SELECT encode(ST_AsEWKB(ST_GeometryFromText( 'LINESTRING(0 0 0,1 0 0,1 1 2)')), 'hex');
SELECT ST_AsGeoJSON(ST_GeomFromGML('<gml:Point><gml:coordinates>1,1</gml:coordinates></gml:Point>'));
⑨ Casting from Text
SELECT 0.9::text; SELECT 'POINT(0 0)'::geometry; SELECT 'SRID=4326;POINT(0 0)'::geometry;

IV-3-1. Geometry
 Geometry 연습문제 사용할 공간함수
70
 sum(expression) aggregate to return a sum for a set of
records
 count(expression) aggregate to return the size of a set of
records
 ST_GeometryType(geometry) returns the type of the
geometry
 ST_NDims(geometry) returns the number of dimensions of
the geometry
 ST_SRID(geometry) returns the spatial reference identifier
number of the geometry
 ST_X(point) returns the X ordinate
 ST_Y(point) returns the Y ordinate
 ST_Length(linestring) returns the length of the linestring
 ST_StartPoint(geometry) returns the first coordinate as a
point
 ST_EndPoint(geometry) returns the last coordinate as a point
 ST_NPoints(geometry) returns the number of coordinates in
the linestring
 ST_Area(geometry) returns the area of the polygons
 ST_NRings(geometry) returns the number of rings (usually 1,
more if there are holes)
 ST_ExteriorRing(polygon) returns the outer ring as a
linestring
 ST_InteriorRingN(polygon, integer) returns a specified
interior ring as a linestring
 ST_Perimeter(geometry) returns the length of all the rings
 ST_NumGeometries(multi/geomcollection) returns the
number of parts in the collection
 ST_GeometryN(geometry, integer) returns the specified part
of the collection
 ST_GeomFromText(text) returns geometry
 ST_AsText(geometry) returns WKT text
 ST_AsEWKT(geometry) returns EWKT text
 ST_GeomFromWKB(bytea) returns geometry
 ST_AsBinary(geometry) returns WKB bytea
 ST_AsEWKB(geometry) returns EWKB bytea
 ST_GeomFromGML(text) returns geometry
 ST_AsGML(geometry) returns GML text
 ST_GeomFromKML(text) returns geometry
 ST_AsKML(geometry) returns KML text
 ST_AsGeoJSON(geometry) returns JSON text
 ST_AsSVG(geometry) returns SVG text

IV-3-1. Geometry
 Geometry 연습문제
71
 Nyc 데이터베이스 사용, 사용 테이블
 nyc_census_blocks
– blkid, popn_total, boroname, geom
 nyc_streets
– name, type, geom
 nyc_subway_stations
– name, geom
 nyc_neighborhoods
– name, boroname, geom
① ‘West Village’ 지역(neighborhood)의 면적은 ?
- nyc_neighborhoods
② ‘Manhattan’의 면적은 km 표기 ?(기본단위 m)
- nyc_neighborhoods, nyc_census_blocks
③ 뉴욕시의 얼마나 많은 인구조사 블록(hole)이 있는가?
- nyc_census_blocks
④ 뉴욕시의 총 도로의 길이는 km 표기 ?
- nyc_streets
⑤ ‘Columbus Cir’ 도로의 길이는 ?
- nyc_streets
⑥ ‘West Village’의 boundary를 JSON으로 표현 ?
- nyc_neighborhoods
⑦ ‘West Village’ 다중 폴리곤(Multipolygon) 몇 개 ?
- nyc_neighborhoods
⑧ 뉴욕시의 도로타입별 총 길이는 ?
- nyc_streets

IV-3-2. Spatial Relationships / Joins / Indexing / Projecting
 Spatial Relationships
72
① ST_Equals
- SELECT name, geom, ST_AsText(geom) FROM
nyc_subway_stations WHERE name = 'Broad St';
- SELECT name FROM nyc_subway_stations WHERE
ST_Equals(geom,
'0101000020266900000EEBD4CF27CF2141BC17D69516315141');
② ST_Intersects
- SELECT name, ST_AsText(geom) FROM nyc_subway_stations
WHERE name = 'Broad St';
- SELECT name, boroname FROM nyc_neighborhoods WHERE
ST_Intersects(geom, ST_GeomFromText('POINT(583571
4506714)',26918));

73
③ ST_Disjoint ④ ST_Crosses

74
⑤ ST_Overlaps ⑥ ST_Touches

75
⑦ ST_Within and ST_Contains ⑧ ST_Distance and ST_Dwithin
- SELECT ST_Distance( ST_GeometryFromText('POINT(0 5)'),
ST_GeometryFromText('LINESTRING(-2 2, 2 2)'));
- SELECT name FROM nyc_streets WHERE ST_DWithin( geom,
ST_GeomFromText('POINT(583571 4506714)',26918), 10 );

 Spatial Relationships 연습문제 사용할 공간함수
76
 sum(expression) aggregate to return a sum for a set of
records
 count(expression) aggregate to return the size of a set of
records
 ST_Contains(geometry A, geometry B) returns true if
geometry A contains geometry B
 ST_Crosses(geometry A, geometry B) returns true if
geometry A crosses geometry B
 ST_Disjoint(geometry A , geometry B) returns true if the
geometries do not “spatially intersect”
 ST_Distance(geometry A, geometry B) returns the minimum
distance between geometry A and geometry B
 ST_DWithin(geometry A, geometry B, radius) returns true if
geometry A is radius distance or less from geometry B
 ST_Equals(geometry A, geometry B) returns true if geometry
A is the same as geometry B
 ST_Intersects(geometry A, geometry B) returns true if
geometry A intersects geometry B
 ST_Overlaps(geometry A, geometry B) returns true if
geometry A and geometry B share space, but are not
completely contained by each other.
 ST_Touches(geometry A, geometry B) returns true if the
boundary of geometry A touches geometry B
 ST_Within(geometry A, geometry B) returns true if geometry
A is within geometry B

 Spatial Relationships 연습문제
77
– name, popn_total, boroname, geom
 nyc_streets
– name, routes, geom
① ‘Atlantic Commons’ 이름의 도로의 Geometry 값은?
- nyc_streets
② ‘Atlantic Commons’d의 지역, 자치구는 ?
- nyc_neighborhoods
③ ‘Atlantic Commons’도로와 만나는 도로의 이름은?
- nyc_streets
④ ‘Atlantic Commons’ 반경 50m 이내의 인구수 ?
- nyc_census_blocks

 Spatial Joins
78
① Join
SELECT
subways.name AS subway_name,
neighborhoods.name AS neighborhood_name,
neighborhoods.boroname AS borough
FROM nyc_neighborhoods AS neighborhoods
JOIN nyc_subway_stations AS subways
ON ST_Contains(neighborhoods.geom, subways.geom)
WHERE subways.name = 'Broad St';
② Join and Summarize
‘Manhattan 지역의 총 인구수와 백인/흑인의 비율 ?
SELECT
neighborhoods.name AS neighborhood_name,
Sum(census.popn_total) AS population,
Round(100.0 * Sum(census.popn_white) /
Sum(census.popn_total),1) AS white_pct,
Round(100.0 * Sum(census.popn_black) /
Sum(census.popn_total),1) AS black_pct
FROM nyc_neighborhoods AS neighborhoods
JOIN nyc_census_blocks AS census
ON ST_Intersects(neighborhoods.geom, census.geom)
WHERE neighborhoods.boroname = 'Manhattan'
GROUP BY neighborhoods.name
ORDER BY white_pct DESC;

 Spatial Joins
79
③ Join and Summarize
A지하철의 반경 200m이내의 총인구, 인종별 비율?
SELECT
100.0 * Sum(popn_white) / Sum(popn_total) AS
white_pct,
100.0 * Sum(popn_black) / Sum(popn_total) AS
black_pct,
Sum(popn_total) AS popn_total
FROM nyc_census_blocks AS census
JOIN nyc_subway_stations AS subways
ON ST_DWithin(census.geom, subways.geom, 200)
WHERE strpos(subways.routes,'A') > 0;
 Spatial Joins 연습문제 사용할 공간함수
 sum(expression): aggregate to return a sum for a set of
records
 count(expression): aggregate to return the size of a set of
records
 ST_Area(geometry) returns the area of the polygons
 ST_Contains(geometry A, geometry B) returns the true if
geometry A contains geometry B
 ST_Distance(geometry A, geometry B) returns the minimum
distance between geometry A and geometry B
 ST_DWithin(geometry A, geometry B, radius) returns the
true if geometry A is radius distance or less from geometry B
 ST_Intersects(geometry A, geometry B) returns the true if
geometry A intersects geometry B
 ST_Length(linestring) returns the length of the linestring
 ST_Touches(geometry A, geometry B) returns the true if the
boundary of geometry A touches geometry B
 ST_Within(geometry A, geometry B) returns the true if
geometry A is within geometry B

 Spatial Joins 연습문제
80
 nyc_streets
– name, routes, geom
① ‘Little Italy’ 무슨 역이고, 어떤 노선 인가?
- nyc_subway_stations, nyc_subway_stations
② 6-train 지나는 모든 지역은 어디인가?
③ ‘Battery Park’ 의 총인구?
④ ‘Upper West Side’, ‘Upper East Side’ 인구밀도는 ?

 Spatial Indexing
81
① Spatial Indexing 테스트
- DROP INDEX nyc_census_blocks_geom_gist;
- SELECT
blocks.blkid
FROM nyc_census_blocks blocks
JOIN nyc_subway_stations subways
ON ST_Contains(blocks.geom, subways.geom)
WHERE subways.name = 'Broad St';
- Query 시간 확인
- CREATE INDEX nyc_census_blocks_geom_gist
ON nyc_census_blocks USING GIST (geom);
- 위의 Select 문을 실행 시켜 Query 시간을 확인
② Index-Only Queris
- PostGIS index 내장 공간함수 제공
(ST_Contains, ST_Intersects, ST_DWithin, etc)
- Index 와 ‘&&’ 연산자
SELECT
Sum(popn_total)
FROM nyc_neighborhoods neighborhoods
JOIN nyc_census_blocks blocks
ON neighborhoods.geom && blocks.geom
WHERE neighborhoods.name = 'West Village';
SELECT
Sum(popn_total)
FROM nyc_neighborhoods neighborhoods
JOIN nyc_census_blocks blocks
ON ST_Intersects(neighborhoods.geom, blocks.geom)
WHERE neighborhoods.name = 'West Village';

 Projecting 연습문제 사용할 공간함수
82
 sum(expression) aggregate to return a sum for a set
of records
 ST_Length(linestring) returns the length of the
linestring
 ST_SRID(geometry, srid) returns the SRID of the
geometry
 ST_Transform(geometry, srid) converts geometries
into different spatial reference systems
 ST_AsGML(geometry) returns GML text
 nyc_streets
– name, geom
① 뉴욕시 모든 도로 길이는 ?
- nyc_streets
② SRID 2831로 변환된 뉴욕시 모든 도로 길이는?
- nyc_streets
③ ‘Broad St’ subway station을 KML 표시 ?
- nyc_subway_stations
 Projecting 연습문제

IV-3-3. Geograpy
 Gemotry & Geograpy
83
① 거리 구하기
- SELECT ST_Distance(
ST_GeometryFromText('POINT(-118.4079 33.9434)', 4326), -- Los
Angeles (LAX)
ST_GeometryFromText('POINT(2.5559 49.0083)', 4326) -- Paris
(CDG) );
ST_GeographyFromText('POINT(-118.4079 33.9434)'), -- Los
Angeles (LAX)
ST_GeographyFromText('POINT(2.5559 49.0083)') -- Paris (CDG) );
SELECT ST_Distance(
ST_GeographyFromText('LINESTRING(-118.4079 33.9434, 2.5559
49.0083)'), -- LAX-CDG
ST_GeographyFromText('POINT(-21.8628 64.1286)') -- Iceland );
ST_GeometryFromText('Point(-118.4079 33.9434)'), -- LAX
ST_GeometryFromText('Point(139.733 35.567)')) -- NRT
(Tokyo/Narita) AS geometry_distance,
ST_Distance(
ST_GeographyFromText('Point(-118.4079 33.9434)'), -- LAX
ST_GeographyFromText('Point(139.733 35.567)')) -- NRT
(Tokyo/Narita) AS geography_distance;

IV-3-3. Geograpy
 Gemotry & Geograpy
84
② Geograpy 테이블 생성
-CREATE TABLE airports (
code VARCHAR(3),
geog GEOGRAPHY(Point)
);
INSERT INTO airports VALUES ('LAX', 'POINT(-118.4079
33.9434)');
INSERT INTO airports VALUES ('CDG', 'POINT(2.5559 49.0083)');
INSERT INTO airports VALUES ('REK', 'POINT(-21.8628
64.1286)');
- SELECT * FROM geography_columns;
③ Geometry 변환
- SELECT code, ST_X(geog::geometry) AS longitude FROM
airports;

IV-3-4. Geometry Constructing Functions
 ST_Centroid / ST_PointOnSurface
85
 ST_Buffer
CREATE TABLE liberty_island_zone AS
SELECT ST_Buffer(geom,500)::geometry(Polygon,26918) AS
geom
FROM nyc_census_blocks
WHERE blkid = '360610001001001';

IV-3-4. Geometry Constructing Functions
 ST_Intersection
86
SELECT ST_AsText(ST_Intersection(
ST_Buffer('POINT(0 0)', 2),
ST_Buffer('POINT(3 0)', 2) )
);
SELECT ST_AsText(ST_Union(
ST_Buffer('POINT(0 0)', 2),
ST_Buffer('POINT(3 0)', 2) )
);
CREATE TABLE nyc_census_counties AS SELECT
ST_Union(geom)::Geometry(MultiPolygon,26918) AS geom,
SubStr(blkid,1,5) AS countyid FROM nyc_census_blocks GROUP
BY countyid;
SELECT SubStr(blkid,1,5) AS countyid, Sum(ST_Area(geom)) AS
area FROM nyc_census_blocks GROUP BY countyid;
SELECT countyid, ST_Area(geom) AS area FROM
nyc_census_counties;
SELECT countyid, ST_AsText(geom) FROM nyc_census_counties;
 ST_Union

IV-3-5. More Spatial Joins
 Census Tracts Table 생성
87
① pgAdim 실행 – Query Tool 실행
② C:OpenGISEdupostgisdatanyc 폴더
nyc_census_sociodata.sql 파일 열기
③ [F5] 실행 Census tracts 테이블 생성
④ Refresh 선택, 테이블 추가 확인
⑤ ST_Union을 이용한 새로운 테이블 생성
- CREATE TABLE nyc_census_tract_geoms AS
SELECT ST_Union(geom) AS geom, SubStr(blkid,1,11) AS tractid
FROM nyc_census_blocks
GROUP BY tractid; -- Index the tractid
CREATE INDEX nyc_census_tract_geoms_tractid_idx ON
nyc_census_tract_geoms (tractid);
⑥ Join을 통한 속성정보 추가 테이블 생성
- CREATE TABLE nyc_census_tracts AS
SELECT g.geom, a.*
FROM nyc_census_tract_geoms g
JOIN nyc_census_sociodata a
ON g.tractid = a.tractid; -- Index the geometries
CREATE INDEX nyc_census_tract_gidx ON nyc_census_tracts
USING GIST (geom);
뉴욕 지역의 graduate degrees 사람 비율이 높은 10개 지역은 ?
SELECT Round(100.0 * Sum(t.edu_graduate_dipl) /
Sum(t.edu_total), 1) AS graduate_pct, n.name, n.boroname
FROM nyc_neighborhoods n JOIN nyc_census_tracts t ON
ST_Intersects(n.geom, t.geom) WHERE t.edu_total > 0 GROUP
BY n.name, n.boroname ORDER BY graduate_pct DESC LIMIT
10;
 문제

IV-3-5. More Spatial Joins
 Polygon/Polygon Joins
88
SELECT
Round(100.0 * Sum(t.edu_graduate_dipl) / Sum(t.edu_total), 1)
AS graduate_pct, n.name, n.boroname
FROM nyc_neighborhoods n
JOIN nyc_census_tracts t
ON ST_Contains(n.geom, ST_Centroid(t.geom))
WHERE t.edu_total > 0
GROUP BY n.name, n.boroname
ORDER BY graduate_pct DESC LIMIT 10;
① SELECT Sum(popn_total) FROM nyc_census_blocks;
② SELECT Sum(popn_total)
FROM nyc_census_blocks census
JOIN nyc_subway_stations subway
ON ST_DWithin(census.geom, subway.geom, 500);
③ WITH distinct_blocks AS (
SELECT DISTINCT ON (blkid) popn_total
FROM nyc_census_blocks census
JOIN nyc_subway_stations subway
ON ST_DWithin(census.geom, subway.geom, 500) )
SELECT Sum(popn_total) FROM distinct_blocks;
 큰 반경 거리 Join

 Raster Management (http://postgis.net/docs/manual-2.1/RT_reference.html#Raster_Management_Functions)
89
 AddRasterConstraints — Adds raster constraints to a loaded raster table for a specific column that constrains spatial
ref, scaling, blocksize, alignment, bands, band type and a flag to denote if raster column is regularly blocked. The
table must be loaded with data for the constraints to be inferred. Returns true of the constraint setting was
accomplished and if issues a notice.
 DropRasterConstraints — Drops PostGIS raster constraints that refer to a raster table column. Useful if you need to
reload data or update your raster column data.
 PostGIS_Raster_Lib_Build_Date — Reports full raster library build date.
 PostGIS_Raster_Lib_Version — Reports full raster version and build configuration infos.
 ST_GDALDrivers — Returns a list of raster formats supported by your lib gdal. These are the formats you can output
your raster using ST_AsGDALRaster.
 UpdateRasterSRID — Change the SRID of all rasters in the user-specified column and table.

 Raster Constructors (http://postgis.net/docs/manual-2.1/RT_reference.html#Raster_Constructors)
90
 ST_AddBand — Returns a raster with the new band(s) of given type added with given initial value in the given index
location. If no index is specified, the band is added to the end.
 ST_AsRaster — Converts a PostGIS geometry to a PostGIS raster.
 ST_Band — Returns one or more bands of an existing raster as a new raster. Useful for building new rasters from
existing rasters.
 ST_MakeEmptyRaster — Returns an empty raster (having no bands) of given dimensions (width & height), upperleft
X and Y, pixel size and rotation (scalex, scaley, skewx & skewy) and reference system (srid). If a raster is passed in,
returns a new raster with the same size, alignment and SRID. If srid is left out, the spatial ref is set to unknown (0).
 ST_Tile — Returns a set of rasters resulting from the split of the input raster based upon the desired dimensions of
the output rasters.
 ST_FromGDALRaster — Returns a raster from a supported GDAL raster file.

 Raster Accessors (http://postgis.net/docs/manual-2.1/RT_reference.html#Raster_Accessors)
91
 ST_GeoReference — Returns the georeference meta data in GDAL or ESRI format as commonly seen in a world file.
Default is GDAL.
 ST_Height — Returns the height of the raster in pixels.
 ST_IsEmpty — Returns true if the raster is empty (width = 0 and height = 0). Otherwise, returns false.
 ST_MetaData — Returns basic meta data about a raster object such as pixel size, rotation (skew), upper, lower left,
etc.
 ST_NumBands — Returns the number of bands in the raster object.
 ST_PixelHeight — Returns the pixel height in geometric units of the spatial reference system.
 ST_PixelWidth — Returns the pixel width in geometric units of the spatial reference system.
 ST_ScaleX — Returns the X component of the pixel width in units of coordinate reference system.
 ST_ScaleY — Returns the Y component of the pixel height in units of coordinate reference system.
 ST_RasterToWorldCoord — Returns the raster's upper left corner as geometric X and Y (longitude and latitude) given
a column and row. Column and row starts at 1.
 ST_RasterToWorldCoordX — Returns the geometric X coordinate upper left of a raster, column and row. Numbering
of columns and rows starts at 1.
 ST_RasterToWorldCoordY — Returns the geometric Y coordinate upper left corner of a raster, column and row.
Numbering of columns and rows starts at 1.
 ST_Rotation — Returns the rotation of the raster in radian.
 ST_SkewX — Returns the georeference X skew (or rotation parameter).
 ST_SkewY — Returns the georeference Y skew (or rotation parameter).

 Raster Accessors (http://postgis.net/docs/manual-2.1/RT_reference.html#Raster_Accessors)
92
 ST_SRID — Returns the spatial reference identifier of the raster as defined in spatial_ref_sys table.
 ST_Summary — Returns a text summary of the contents of the raster.
 ST_UpperLeftX — Returns the upper left X coordinate of raster in projected spatial ref.
 ST_UpperLeftY — Returns the upper left Y coordinate of raster in projected spatial ref.
 ST_Width — Returns the width of the raster in pixels.
 ST_WorldToRasterCoord — Returns the upper left corner as column and row given geometric X and Y (longitude and
latitude) or a point geometry expressed in the spatial reference coordinate system of the raster.
 ST_WorldToRasterCoordX — Returns the column in the raster of the point geometry (pt) or a X and Y world
coordinate (xw, yw) represented in world spatial reference system of raster.
 ST_WorldToRasterCoordY — Returns the row in the raster of the point geometry (pt) or a X and Y world coordinate
(xw, yw) represented in world spatial reference system of raster.

 Raster Band Accessors (http://postgis.net/docs/manual-2.1/RT_reference.html#RasterBand_Accessors)
93
 ST_BandMetaData — Returns basic meta data for a specific raster band. band num 1 is assumed if none-specified.
 ST_BandNoDataValue — Returns the value in a given band that represents no data. If no band num 1 is assumed.
 ST_BandIsNoData — Returns true if the band is filled with only nodata values.
 ST_BandPath — Returns system file path to a band stored in file system. If no bandnum specified, 1 is assumed.
 ST_BandPixelType — Returns the type of pixel for given band. If no bandnum specified, 1 is assumed.
 ST_HasNoBand — Returns true if there is no band with given band number. If no band number is specified, then
band number 1 is assumed.

 Raster Pixel Accessors and Setters (http://postgis.net/docs/manual-2.1/RT_reference.html#Raster_Pixel_Accessors)
94
 ST_PixelAsPolygon — Returns the polygon geometry that bounds the pixel for a particular row and column.
 ST_PixelAsPolygons — Returns the polygon geometry that bounds every pixel of a raster band along with the value,
the X and the Y raster coordinates of each pixel.
 ST_PixelAsPoint — Returns a point geometry of the pixel's upper-left corner.
 ST_PixelAsPoints — Returns a point geometry for each pixel of a raster band along with the value, the X and the Y
raster coordinates of each pixel. The coordinates of the point geometry are of the pixel's upper-left corner.
 ST_PixelAsCentroid — Returns the centroid (point geometry) of the area represented by a pixel.
 ST_PixelAsCentroids — Returns the centroid (point geometry) for each pixel of a raster band along with the value,
the X and the Y raster coordinates of each pixel. The point geometry is the centroid of the area represented by a
pixel.
 ST_Value — Returns the value of a given band in a given columnx, rowy pixel or at a particular geometric point.
Band numbers start at 1 and assumed to be 1 if not specified. If exclude_nodata_value is set to false, then all pixels
include nodata pixels are considered to intersect and return value. If exclude_nodata_value is not passed in then
reads it from metadata of raster.
 ST_NearestValue — Returns the nearest non-NODATA value of a given band's pixel specified by a columnx and rowy
or a geometric point expressed in the same spatial reference coordinate system as the raster.
 ST_Neighborhood — Returns a 2-D double precision array of the non-NODATA values around a given band's pixel
specified by either a columnX and rowY or a geometric point expressed in the same spatial reference coordinate
system as the raster.
 ST_SetValue — Returns modified raster resulting from setting the value of a given band in a given columnx, rowy
pixel or the pixels that intersect a particular geometry. Band numbers start at 1 and assumed to be 1 if not specified.

 Raster Pixel Accessors and Setters (http://postgis.net/docs/manual-2.1/RT_reference.html#Raster_Pixel_Accessors)
95
 ST_SetValues — Returns modified raster resulting from setting the values of a given band.
 ST_DumpValues — Get the values of the specified band as a 2-dimension array.
 ST_PixelOfValue — Get the columnx, rowy coordinates of the pixel whose value equals the search value.

 Raster Editors (http://postgis.net/docs/manual-2.1/RT_reference.html#Raster_Editors)
96
 ST_SetGeoReference — Set Georeference 6 georeference parameters in a single call. Numbers should be separated
by white space. Accepts inputs in GDAL or ESRI format. Default is GDAL.
 ST_SetRotation — Set the rotation of the raster in radian.
 ST_SetScale — Sets the X and Y size of pixels in units of coordinate reference system. Number units/pixel
width/height.
 ST_SetSkew — Sets the georeference X and Y skew (or rotation parameter). If only one is passed in, sets X and Y to
the same value.
 ST_SetSRID — Sets the SRID of a raster to a particular integer srid defined in the spatial_ref_sys table.
 ST_SetUpperLeft — Sets the value of the upper left corner of the pixel to projected X and Y coordinates.
 ST_Resample — Resample a raster using a specified resampling algorithm, new dimensions, an arbitrary grid corner
and a set of raster georeferencing attributes defined or borrowed from another raster.
 ST_Rescale — Resample a raster by adjusting only its scale (or pixel size). New pixel values are computed using the
NearestNeighbor (english or american spelling), Bilinear, Cubic, CubicSpline or Lanczos resampling algorithm. Default
is NearestNeighbor.
 ST_Reskew — Resample a raster by adjusting only its skew (or rotation parameters). New pixel values are computed
using the NearestNeighbor (english or american spelling), Bilinear, Cubic, CubicSpline or Lanczos resampling
algorithm. Default is NearestNeighbor.
 ST_SnapToGrid — Resample a raster by snapping it to a grid. New pixel values are computed using the
NearestNeighbor (english or american spelling), Bilinear, Cubic, CubicSpline or Lanczos resampling algorithm. Default
is NearestNeighbor.

 Raster Editors (http://postgis.net/docs/manual-2.1/RT_reference.html#Raster_Editors)
97
 ST_Resize — Resize a raster to a new width/height
 ST_Transform — Reprojects a raster in a known spatial reference system to another known spatial reference system
using specified resampling algorithm. Options are NearestNeighbor, Bilinear, Cubic, CubicSpline, Lanczos defaulting
to NearestNeighbor.

 Raster Band Editors (http://postgis.net/docs/manual-2.1/RT_reference.html#RasterBand_Editors)
98
 ST_SetBandNoDataValue — Sets the value for the given band that represents no data. Band 1 is assumed if no band
is specified. To mark a band as having no nodata value, set the nodata value = NULL.
 ST_SetBandIsNoData — Sets the isnodata flag of the band to TRUE.

 Raster Band Statistics and Analytics (http://postgis.net/docs/manual-2.1/RT_reference.html#RasterBand_Stats)
99
 ST_Count — Returns the number of pixels in a given band of a raster or raster coverage. If no band is specified
defaults to band 1. If exclude_nodata_value is set to true, will only count pixels that are not equal to the nodata
value.
 ST_Histogram — Returns a set of record summarizing a raster or raster coverage data distribution separate bin
ranges. Number of bins are autocomputed if not specified.
 ST_Quantile — Compute quantiles for a raster or raster table coverage in the context of the sample or population.
Thus, a value could be examined to be at the raster's 25%, 50%, 75% percentile.
 ST_SummaryStats — Returns record consisting of count, sum, mean, stddev, min, max for a given raster band of a
raster or raster coverage. Band 1 is assumed is no band is specified.
 ST_ValueCount — Returns a set of records containing a pixel band value and count of the number of pixels in a
given band of a raster (or a raster coverage) that have a given set of values. If no band is specified defaults to band
1. By default nodata value pixels are not counted. and all other values in the pixel are output and pixel band values
are rounded to the nearest integer.

 Raster Outputs (http://postgis.net/docs/manual-2.1/RT_reference.html#Raster_Outputs)
100
 ST_AsBinary — Return the Well-Known Binary (WKB) representation of the raster without SRID meta data.
 ST_AsGDALRaster — Return the raster tile in the designated GDAL Raster format. Raster formats are one of those
supported by your compiled library. Use ST_GDALRasters() to get a list of formats supported by your library.
 ST_AsJPEG — Return the raster tile selected bands as a single Joint Photographic Exports Group (JPEG) image (byte
array). If no band is specified and 1 or more than 3 bands, then only the first band is used. If only 3 bands then all 3
bands are used and mapped to RGB.
 ST_AsPNG — Return the raster tile selected bands as a single portable network graphics (PNG) image (byte array). If
1, 3, or 4 bands in raster and no bands are specified, then all bands are used. If more 2 or more than 4 bands and
no bands specified, then only band 1 is used. Bands are mapped to RGB or RGBA space.
 ST_AsTIFF — Return the raster selected bands as a single TIFF image (byte array). If no band is specified, then will try
to use all bands.

 Raster Processing - Map Algebra (http://postgis.net/docs/manual-2.1/RT_reference.html#Raster_Processing_MapAlgebra)
101
 ST_Clip — Returns the raster clipped by the input geometry. If band number not is specified, all bands are
processed. If crop is not specified or TRUE, the output raster is cropped.
 ST_ColorMap — Creates a new raster of up to four 8BUI bands (grayscale, RGB, RGBA) from the source raster and a
specified band. Band 1 is assumed if not specified.
 ST_Intersection — Returns a raster or a set of geometry-pixelvalue pairs representing the shared portion of two
rasters or the geometrical intersection of a vectorization of the raster and a geometry.
 ST_MapAlgebra — Callback function version - Returns a one-band raster given one or more input rasters, band
indexes and one user-specified callback function.
 ST_MapAlgebra — Expression version - Returns a one-band raster given one or two input rasters, band indexes and
one or more user-specified SQL expressions.
 ST_MapAlgebraExpr — 1 raster band version: Creates a new one band raster formed by applying a valid PostgreSQL
algebraic operation on the input raster band and of pixeltype provided. Band 1 is assumed if no band is specified.
 ST_MapAlgebraExpr — 2 raster band version: Creates a new one band raster formed by applying a valid PostgreSQL
algebraic operation on the two input raster bands and of pixeltype provided. band 1 of each raster is assumed if no
band numbers are specified. The resulting raster will be aligned (scale, skew and pixel corners) on the grid defined
by the first raster and have its extent defined by the "extenttype" parameter. Values for "extenttype" can be:
INTERSECTION, UNION, FIRST, SECOND.
 ST_MapAlgebraFct — 1 band version - Creates a new one band raster formed by applying a valid PostgreSQL
function on the input raster band and of pixeltype prodived. Band 1 is assumed if no band is specified.
 ST_MapAlgebraFct — 2 band version - Creates a new one band raster formed by applying a valid PostgreSQL
function on the 2 input raster bands and of pixeltype prodived. Band 1 is assumed if no band is specified. Extent
type defaults to INTERSECTION if not specified.

 Raster Processing - Map Algebra (http://postgis.net/docs/manual-2.1/RT_reference.html#Raster_Processing_MapAlgebra)
102
 ST_MapAlgebraFctNgb — 1-band version: Map Algebra Nearest Neighbor using user-defined PostgreSQL function.
Return a raster which values are the result of a PLPGSQL user function involving a neighborhood of values from the
input raster band.
 ST_Reclass — Creates a new raster composed of band types reclassified from original. The nband is the band to be
changed. If nband is not specified assumed to be 1. All other bands are returned unchanged. Use case: convert a
16BUI band to a 8BUI and so forth for simpler rendering as viewable formats.
 ST_Union — Returns the union of a set of raster tiles into a single raster composed of 1 or more bands.

 Raster Processing - Built-in Map Algebra Callback Functions
103
 ST_Distinct4ma — Raster processing function that calculates the number of unique pixel values in a neighborhood.
 ST_InvDistWeight4ma — Raster processing function that interpolates a pixel's value from the pixel's neighborhood.
 ST_Max4ma — Raster processing function that calculates the maximum pixel value in a neighborhood.
 ST_Mean4ma — Raster processing function that calculates the mean pixel value in a neighborhood.
 ST_Min4ma — Raster processing function that calculates the minimum pixel value in a neighborhood.
 ST_MinDist4ma — Raster processing function that returns the minimum distance (in number of pixels) between the
pixel of interest and a neighboring pixel with value.
 ST_Range4ma — Raster processing function that calculates the range of pixel values in a neighborhood.
 ST_StdDev4ma — Raster processing function that calculates the standard deviation of pixel values in a
neighborhood.
 ST_Sum4ma — Raster processing function that calculates the sum of all pixel values in a neighborhood.

 Raster Processing - DEM (Elevation)
104
 ST_Aspect — Returns the aspect (in degrees by default) of an elevation raster band. Useful for analyzing terrain.
 ST_HillShade — Returns the hypothetical illumination of an elevation raster band using provided azimuth, altitude,
brightness and scale inputs.
 ST_Roughness — Returns a raster with the calculated "roughness" of a DEM.
 ST_Slope — Returns the slope (in degrees by default) of an elevation raster band. Useful for analyzing terrain.
 ST_TPI — Returns a raster with the calculated Topographic Position Index.
 ST_TRI — Returns a raster with the calculated Terrain Ruggedness Index.

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