Choosing the Correct Dataset

The type of database used by the organisation. For example if SQL Server Spatial is installed, users should use the Microsoft SQL Server Spatial dataset to read or export data to SQL Server.

It is usually cost-effective for an organisation to continue using the corporate database for all spatial data storage requirements.

This is desirable for a number of reasons:

• The organisation has existing knowledge of the database
• If the organisation has a corporate licence for the database, additional licences are not needed.

Processing spatial data can be CPU and disk I/O intensive, hence we recommend making a new installation of the database on a dedicated server.

If no corporate database is available, users should test each database to determine its suitability.

Oracle and SQL Server can be installed using temporary trial licences. Oracle Express edition and SQL Server Express are free cut down database versions but come with spatial capabilities.

PostgreSQL is freeware and can be used without a licence.

Users who work with and store topology are restricted to using the Editable Geometry dataset. This dataset allows data to be stored in either Oracle, SQL Server, PostGIS or Access:

• Oracle (not spatial or locator). Spatial data is stored using the Binary Large Object type (BLOB), this is not the same as storing data in Oracle SDO_Geometry type.
• PostGIS (not spatial) Spatial data is stored using the BYTEA type, this is not the same as storing data in PostGIS Geometry type.
• SQL Server 2000 and above (not spatial in SQL Server 2008).
  

Users choice of dataset may be influenced by other GIS and IT systems used by the organisation.

Users can copy data from one format to another.

For example you can read data from Oracle and save it in another format. This can be another database format such as Microsoft Access or a BDS file.

With the data being local to the pc/laptop it is possible to continue working with the data whilst off site.