I need to create a GIS document showing dots (already have a DB with coordinates) and information on brazilian map.

Question

I have a database with coordinates (latitude and longitude, for example [-45,27064309, -19,7832029]) and I need to show them as dots over the brazilian map. I also need to show some information about the dots when I'm over the dots with the mouse. I would like also to use a GeoJSON file to show the different states and regions of Brazil and maybe a consolidate information on this. I have already tried to use several JSON files on Knowage, but it seems that the files are not in the correct pattern. Can you help me with this?

Answer 1

Dear Luciano,

Are you using the Layer catalog to manage the GeoJson file ?
And how did you create the gis file ?

let me know

Angelo

Comments

I have downloaded the GIS file from the internet. There are a lot of Brazil GeoJSON file on the internet. I have tested the file on the site http://geojson.io/#map=4/-12.00/-56.07 and it seems to be working well.
I am using the layer catalog on Knowage.I named it Brasil_map on my knowage and selected layer id "estados" and layer order "1".

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OK, we are trying to load your GeoJson, but in order to show POINT readed from DB, you MUST configure GeoServer that produce the layer and add this layer on Layer Catalog.

A.

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Is not possible to get only the coordinates from the database as a resultset? Maybe I could create a GeoJSON file with the data only to use for the PoC now to show it as an example to the client.

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Hi Luciano,
Yes, you have to use geo server to create a layer
A.

Answer 2

Hi, 
   please check the EPSG code value of the geojson file. It must  be EPSG:4326 such as:

"crs":{"type":"EPSG","properties":{"code":"4326"}}

Usually, I download shape file and convert it into geojson trough the GeoServer (http://docs.geoserver.org/stable/en/user/gettingstarted/shapefile-quickstart/). 

But surely there will be other tools to make this conversion.

Comments

I have installed the geoserver and used it to provide the map areas. Now I can see the areas using a Gis Document on Knowage. First objective achieved. Now I need to show some dots (I have the coordinates) and  information about the dots when I'm over them with the mouse.

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Considering that now you have geoserver you could use it to create a new datasource onto a spatial db table (for example with postgis a good free open source database).
After that you can choose if use it in a dynamic way (for example calling the layer through a WFS service) or if create a static geojson file (in the same way you made last time). In both ways you will be able to create a gis layer onto knowage and use it for your new map.

Hope these help.

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seemed showing dots on map with information might be a popular needs in marketplace   (dot data reading from database as dynamic datasets, instead of static geojson data ).   would you advice how to make that in Knowage?

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Knowage is able to call SWF or WMS services... so, about the Knowage side, you have only to create a layer into the catalog with the right configuration (see more details onto the documentation released). Instead about all other components such as spatial db or gis server, depends from the user project context, so I cannot give specific details.

Anyway, you are able to find some information about the management of these context components at:
- http://postgis.refractions.net/documentation/manual-1.3/ch04.html
- https://postgis.net/docs/using_postgis_dbmanagement.html
- http://docs.geoserver.org/latest/en/user/services/index.html#services

Regards.

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got it. thanks. I'd try it later.     by the way, many other BI tools can directly show the dot data on map. and the dot coordination info like latitude, longitude and other biz info come from outside data sources, like Excel, CSV or database....not sure if Knowage can make that easily?

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Yes, Knowage is able to show data and layer details directly on the map ... the unique difference is that the system joins business data with layer data trhough only one property (for example a state code)... so you aren't able to pass your own longitude and latitude directly...
You can see an example on the demo on-line at https://demo.knowage-suite.com/knowage/servlet/AdapterHTTP?PAGE=LoginPage&NEW_SESSION=TRUE#
 (you have to execute the document 'USA Map' under 'Dynamic Map' folder).
In this document  measures are shown as coloured area - as default - but it's possible show them as point (where the dimension is relative to the measure value) or as charts .