Managing Spatial Data Sources

Updating spatial data sources

Before a spatial data source can be used to create layers, it must be updated. In JMap, updating a data source generally involves collecting information on the spatial data and its attributes and preparing data for fast and efficient access. This process may be very brief or may take several minutes, depending on the type of data source and amount of data. Updating data sources that read data files usually takes more time, in proportion to the size of the files. Data sources that read data from servers can usually be updated very quickly.

In JMap Admin, you can update a data source by clicking on Update in its information section. You can also update several data sources simultaneously by selecting them in the section displaying the list of data sources and clicking on Update.

Scheduling automatic data source updates

You can schedule automatic data source updates. This action may be helpful if you use data sources that read data files. If the files are frequently modified, you can schedule automatic updates that will occur on a regular basis (every day at midnight, for instance) for the appropriate data sources. Each data source can have its own schedule.

In order to schedule updates for a given data source, click on Schedule in that data source's details section. Afterwards, simply follow the wizard to define the specific moments when the updates will take place. Scheduling options are very flexible.

Once these tasks have been scheduled, you can view the current schedule for a data source by viewing its information section.

At any time, you can access the list of all planned updates for data sources by clicking on Scheduler in the JMap Server section.

Deleting spatial data sources

You can delete spatial data sources by clicking on Delete from the data source's information section. You can also delete data sources by selecting them in the section listing the sources and then clicking Delete. When a data source has been deleted, its entire configuration is permanently deleted. The data itself (the file or database) is not affected.

Statuses of spatial data sources

Each spatial data source has a status. The status indicates the condition of the data source, i.e. if it is ready to work, if an error occurred, etc. The status of a newly created data source is always set to not ready (unless you checked the auto-update flag). This means that the data source cannot be used yet. In order to be used, every data source must be updated at least once. Depending on the type of data source and volume of data, the update process can be very fast or can take a certain amount of time.

Data sources can be updated in batches. A maximum of 3 data sources can be updated simultaneously. Other data sources to be updated are queued until they get updated too.

The following table describes the possible statuses of a spatial data source:

 

System spatial data sources

System spatial data sources are data sources that are automatically created by JMap to support JMap data source and layer sharing. Normally, these resources do not need to be managed and they are not displayed by default in the list of spatial data sources. If you wish to display them, you can select Show system data sources in the bottom right portion of the window.