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Draft to compute zonal statistics on area of interest polygon or shape draw on leaflet using PostgreSql and Java - Geometry extracted from leaflet as GeoJson. Polygon- {"type":"Feature","properties":{"desc":null,"image":null},"geometry":{"type":"Polygon","coordinates":[[[-117.103271484375,34.264026473152875],[-117.1142578125,34.14818102254435],[-117.03186035156251,34.10498222546687],[-116.91925048828124,34.14363482031264],[-116.94946289062499,34.25494631082515],[-117.0867919921875,34.252676117101515],[-117.103271484375,34.264026473152875]]]}} {"type":"Feature","properties":{"desc":null,"image":null},"geometry":{"type":"Polygon","coordinates":[[[-116.86981201171875,34.11407854333859],[-116.86981201171875,34.24132422972854],[-116.71874999999999,34.24132422972854],[-116.71874999999999,34.11407854333859],...

Steps for loading a raster in PostGIS (PgSql 9.4/ PostGIS 2.2) and pull it from database to view in QGIS 2.14.17. 1. Generate SQL for raster [NOTE: Do not create PostGIS table name starts with underscore, it creates problem while adding raster to QGIS from PostGIS database using DB Manager]         raster2pgsql -s 4326 -I -C -M -F -t 50x50 -N nan biodiv_ssolnw.tif > biodiv_ssolnw.sql 2. Import generated raster into PostGIS database [Make sure to enable postgis extension in db]          psql -h localhost -U postgres -d ecolservicedb -f biodiv_ssolnw.sql the output is: Processing 1/1: ags_473038164.tif BEGIN CREATE TABLE INSERT 0 1 INSERT 0 1 INSERT 0 1 INSERT 0 1 … … …. CREATE INDEX ANALYZE NOTICE:  Adding SRID constraint CONTEXT:  PL/pgSQL function addrasterconstraints(name,name,name,boolean,boolean,boolean,boolean,boolean,boolean,boolean,boolean,boolean,boolean,boolean,boolean) line 53 at RETURN...

There are two methods to register Database to ArcGIS Server A) Register via ArcGIS Desktop Double click to ensure ArcGIS Server Instance is connected to ArcGIS Desktop Right Click to Publisher connection to ArcGIS Server Then Click ArcGIS Server Properties to open ArcGIS Server Properies Add Data Store in Registered Databases ESRI Video on Registering database data with ArcGIS 10.1 for Server B) Register via ArcGIS Server Manager Web Interface SOURCE:  http://gisdeveloper.blogspot.com/2014_04_01_archive.html  ( Copied here for my future reference) REGISTER DATABASE TO ARCGIS SERVER While publishing data (from database) to ArcGIS server it gives you a warning that 24011: Data source is not registered with the server and data will be copied to the server How to resolve this ?? Well there are different approaches, here is the one which i followed. But before doing anything Please Note: Note: The client side libraries need to be copied to ArcGI...

Start to postgresql :  sudo -u postgres psql postgres List all databases :  \list  or  \l : list all databases \dt : list all tables in the current database Type  \q  and then press  ENTER  to quit  psql Connect to database : \connect database_name Drop all tables from a database:  drop schema public cascade;

#Run from windows command prompt #Create dump into dump.sql C:\Program Files\PostgreSQL\9.4\bin>pg_dump.exe -h localhost -p 5432 -U username dbnameToExport  > D:\dump.sql #Import dump C:\Program Files\PostgreSQL\9.4\bin>psql.exe -h localhost -p 5432 -U postgres dbnameToImport  < D:/dump.sql Password for user postgres : Only super user can create PostGIS extension in PostgreSQL. Reproject Geometry from WGS84 to Web Mercator Aux ALTER TABLE table_name             ALTER COLUMN column_name TYPE geometry(MultiPolygon, 3857) USING                        ST_Transform(ST_SetSRID(column_name,4326),3857) ;  Linux, import Postgresql dump with Postgresql database: psql - h hostname - d databasename - U username - f dump file . sql

Last week I have installed PostgreSql/PostGis and PgAdmin. Once I have tired to import shape file from PgAdmin using "PostGIS Shape file and DBF Loader 2.1" as below. But it throws an error complaining "File import error in PostGis AddGeometry column doesn't exist" as shown in figure below  Then, I found out that the spatial extension is not enabled in my database. The following image shows the steps to enabled the spatial extension in the database.  Open new extension and name it postgis.   Then import the shape file again... Voila it works

Books Pro Cons It provides solid guide to how geospatial analysis work, particularly with respect to GIS. The book emphasizes conceptual workflows and with basic math which is helpful for creating own code and also getting an understanding of what's happening under the hood in contemporary GIS. It is better to have an update because lots of changes in GIS software over last five years. This book is for typical GIS user aspiring to design good maps. It is illustrating GIS map software and throughout with map samples in color which is especially useful for those who has little prior training or experience in map making. This is acceptable book for beginners but very little information of advanced users. It hardly touches on advanced cartographic representations. This book explains the computational geometry and algorithms concisely and very readable. It emphasis on describing algori...

One of my client’s requirements was to create and open source geospatial DBMS to hold utilities and city shape files. As looking through the internet, I found PostGIS is an open source software program that adds support for geographic objects to the PostgreSQL object-relational database.  As project reference, I choose PostGIS in Action , as project accomplished successfully I realized  my judgment was excellent. PostGIS in Action is a very comprehensive introduction to PostGIS for developers of all levels of experience. Basically it is split into 3 parts: Part 1- Nice and slow startup with PostGIS. You can skip this section if you have prior knowledge about any kinds of spatial databases and geometry data types. Part 2- Put PostGIS in work. It contains technical details on proximity analysis, geocoding addresses, manipulating polygons and lines, and scaling and rotating geometries as well as efficient queries and how to tune your database and selectio...

The Geographic Information Science Center of Excellence at South Dakota State University developed a web based West Nile virus (WNV) mapping application using Geosever, Openlayers, PostGIS,GeoWebCache, Jquery, Google visualization APIs, and, other open source technologies. This application allows users to pan, and zoom to visualize historical WNV patterns while using a slider bar to navigate through time. Users can click on counties to see -county level time-series graphs, case counts, and total population. The application also supports changing choropleth transparencies, choropleth classifications, and map backgrounds. Methods: A. OpenGeo tools: i.     Open layers ii.    Geoserver iii.   WebGeoCache iv.   PostGIS B. Google APIs i.       Google Maps API ii.      Google Charting API C.      HTML5 These are frequently refereed to as HTML5 technologies. Javascript HTML Canvas ...

In this section, I am showing the 3 basic steps to connect PostGIS database with a widely used open source desktop based gis, QGIS.  Step1: Install PostGIS with Spatial database support extension i.                     If PostgreSQL is already installed è Launch ‘Application stack builder’ from startup menu in windows 7. ii.                   Select the appropriate instance of PGSQL from dropdown list and Click NEXT. iii.                 Expand ‘Categories’ è Expand ‘Spatial Extensions’ è Select appropriate PostGIS version(1.5)  for the already installed PGSQL version(8.4). iv.                     Follow the instructions to inst...