After completing the instructions in the following sections:
- Creating a Data Source Connection
- Creating a Map Catalog in the DBMS
- Making a DBMS Table Mappable to Display it on a Map
you are ready to connect to your data sources and the database tables you want to work with. If you are not familiar with the details of your remote database type, discuss your requirements with your database administrator to find out the basic information necessary to connect to your database.
Options for Opening Tables
When opening DBMS tables, there are a number of options for:
- Which tables in the database to open or select to open all of the available tables.
- Whether to open the tables live or linked. If selecting linked, you can open them with caching. You can set this option individually for a table to override what is set for all the tables you will open.
- How you want the data to display on the map by selecting point, line, and region style options. You can change: symbol type, color, and size, as well as the label font; line color and pattern; region fill color and pattern, and border color and pattern.
- Column and row filters on tables. Filters let you reduce the amount of information that you will work with and reduce the time it takes to fetch and save the data.
- A directory where the MapInfo TAB file (with the same name as the table) will be saved.
You can apply these selections to all of the tables you will open and also select overrides for individual tables.
Performing Queries on Tables
When performing a query on a table the query executes when:
- Linked tables: Opening the table for the first time, and when refreshing the table.
- Live with cache: Adding the table to the map, and zooming or panning in the map.
- Live without cache: Adding the table to the map, zooming or panning in the map, and clicking in the map with the Select or Info commands.
You can specify which records to retrieve from the database by attribute or by geography. The query syntax is specific to the database that you are accessing. MapInfo Pro translates some expressions when passing a query to the database, such as Object, Within, Selection, and Current_Mapper. You may save your queries, so that you can reuse them.
Tables and Metadata
MapInfo Pro stores information about a table in the .TAB file's metadata, which is not displayed on the map. MapInfo Pro uses metadata to manage transactions between MapInfo Pro and the server database. Two of the most important kinds of information stored in the metadata include the connection string and the query you build from the DBMS Table Wizard, or Expert dialog box.