Spatial Data Sources > Introduction

Introduction

A spatial data source in JMap, as its name implies, is any source that can provide spatial data. Spatial data sources are separated into 2 families : vector data sources and raster data sources. Vector data sources provide vector spatial data along with its attributes and raster data sources provide raster data (images). Configuring data sources is usually the first step to complete to publish spatial data with JMap.

Some spatial data sources work with a file reader to load spatial data from files in various formats (e.g. mif files, shape files, tiff image files). Other data sources access the data stored on distant spatial data servers (e.g. PostGIS, Oracle Spatial/Locator, ArcSDE, WMS/WFS servers, etc.).

Once a spatial data source is created, it must be updated before it can be used. Updating a spatial data source means preparing it for use by JMap Server. In concrete terms, it implies different tasks, depending on the type of data source. Generally speaking, for data sources that access data stored in files, the file contents are read by JMap Server and put inside JMap System database tables. A spatial index is then built for fast access and attribute statistics are calculated. For data sources that access data stored on remote spatial servers like Oracle Spatial/Locator or WFS systems, the update process is simpler and reduced to calculating attribute statistics. Updating file data sources takes more time than updating server data sources.

Spatial data sources are listed in the Spatial data sources section in JMap Admin. The following table presents basic information about each data source. When you click on the name of a data source, a details section is displayed. This section presents some useful information about the spatial data source as well as buttons to perform management tasks.

Spatial data sources
Edit	Starts the edition wizard for the data source.
Make editable	Allows you to transform a spatial data source that reads data files (e.g. SHP, TAB, DWG, etc.) into a JMap Spatial data source. Afterwards, you can use this spatial data source to edit spatial and descriptive data in JMap. Once this transformation has been done, the data source will no longer be linked to the original files. Any changes made to the data must be done directly using JMap's editing tools.
Update	Starts the update process of this data source. See section Managing Spatial Data Sources for more details.
Delete	Deletes the data source. See section Managing Spatial Data Sources for more details.
Metadata	Opens the metadata section. Refer to the Metadata of a Datasource section for more information on this topic.
Permissions	Opens the section allowing you to modify the permissions related to this spatial data source. Refer to the Spatial Data Source Permissions section for more information on this topic.
Schedule	Opens the scheduling section for this data source, allowing you to define schedules for automatic updates of this data source. See the Managing Spatial Data Sources section for more details.
References	Opens a list of all layers that refer to this data source. This is useful to know if a data source is used by some layers before deleting it.