IBM DB2 Spatial Writer Parameters

This is the data source name as configured using the DB2 client software.

Enter the username and password to access the service.

When enabled, the database connection persists for the duration of an FME session.

For example, it may be desirable to maintain a connection when running a batch of 100 workspaces on the same database connection, which saves the processing time required to make and break a database connection.

FME considers the database connection to be the same when the database name, the username, and password are the same.

The time (seconds) after which to terminate a query to the database if it has not yet returned a connection/result.

If it is set to 0, there is no timeout. The default is 30.

Coordinate systems may be extracted from input feature data sources, may come predefined with FME, or may be user-defined. FME allows different output and input coordinate systems, and performs the required coordinate conversions when necessary.

For systems that know their coordinate system, the Coordinate System field will display Read from Source and FME will read the coordinate system from the source dataset. For most other input sources, the field will display Unknown (which simply means that FME will use default values). In most cases, the default value is all you'll need to perform the translation.

You can always choose to override the defaults and choose a new coordinate system. Select More Coordinate Systems from the drop-down menu to open the Coordinate System Gallery.

Changing a Reprojection

To perform a reprojection, FME typically uses the CS-MAP reprojection engine, which includes definitions for thousands of coordinate systems, with a large variety of projections, datums, ellipsoids, and units. However, GIS applications have slightly different algorithms for reprojecting data between different coordinate systems. To ensure that the data FME writes matches exactly to your existing data, you can use the reprojection engine from a different application.

To change the reprojection engine, Select Workspace Parameters > Spatial > Reprojection Engine. In the example shown, you can select Esri (but the selection here depends on your installed applications):

These parameters can be used to set Min X, Min Y, and Scale Factor for all feature types in a writer.

Some features’ geometries may fail the DB2 Spatial Extender’s check constraints based on the offset, scale, and coordinate system values. These features, as well as others with out-of-range or invalid attribute values, will be rejected and cannot be written to the database.

• Yes – The translation will abort immediately after encountering such a problem.
• No – The translation will continue, but the rejected features will not be written to the database.

This parameter allows users to tune the performance of the reader. It specifies how many rows are read from the database at a time.

Features can be read from the DB2 Spatial database using a bulk reading technique to maximize performance. Normally, 1000 rows of data are read from the database at a time. However, when reading LOB (BLOBs or CLOBs) data, FME is restricted to a transaction interval of size 1. Since geometry columns are normally BLOB types, reading of spatial features will not be affected by this directive.

This parameter allows for the execution of SQL statements before writing to a table. For example, it may be necessary to clean up a table before attempting to write to it. The statements will be executed only when the first feature arrives at the writer.

For detailed information about SQL functions, click the corresponding menu item in the SQL to Run editor help.

Tip  If you have enabled FME AI Assist, you can get help creating SQL queries. Click the AI Assist button to open the editor.

Available menu options depend on the format.

Multiple SQL commands can be delimited by a character specified using the FME_SQL_DELIMITER directive, embedded at the beginning of the SQL block. The single character following this directive will be used to split the SQL block into SQL statements, which will then be sent to the database for execution. Note: Include a space before the character.

For example:

FME_SQL_DELIMITER ;
DELETE FROM instructors ;
DELETE FROM people
WHERE LastName='Doe' AND FirstName='John'

Multiple delimiters are not allowed and the delimiter character will be stripped before being sent to the database.

Any errors occurring during the execution of these SQL statements will normally terminate the reader or writer (depending on where the SQL statement is executed) with an error. If the specified statement is preceded by a hyphen (“-”), such errors are ignored.

This parameter allows for the execution of SQL statements after a set of tables has been written. For example, it may be necessary to clean up a temporary view after creating it.

For detailed information about SQL functions, click the corresponding menu item in the SQL to Run editor help.

Tip  If you have enabled FME AI Assist, you can get help creating SQL queries. Click the AI Assist button to open the editor.

Available menu options depend on the format.

Multiple SQL commands can be delimited by a character specified using the FME_SQL_DELIMITER directive, embedded at the beginning of the SQL block. The single character following this directive will be used to split the SQL block into SQL statements, which will then be sent to the database for execution. Note: Include a space before the character.

For example:

FME_SQL_DELIMITER ;
DELETE FROM instructors ;
DELETE FROM people
WHERE LastName='Doe' AND FirstName='John'

Multiple delimiters are not allowed and the delimiter character will be stripped before being sent to the database.

Any errors occurring during the execution of these SQL statements will normally terminate the reader or writer (depending on where the SQL statement is executed) with an error. If the specified statement is preceded by a hyphen (“-”), such errors are ignored.

Sets the global finest grid size for the spatial grid index. If a dataset contains many different tables, but the same finest grid size applies to all of them, then this is a convenient way of setting the finest grid size value.

Sets the global middle grid size for the spatial grid index. If a dataset contains many different tables but the same middle grid size applies to all of them, then this is a convenient way of setting the middle grid size value.

Sets the global coarsest grid size for the spatial grid index. If a dataset contains many different tables but the same coarsest grid size applies to all of them, then this is a convenient way of setting the coarsest grid size value.