SpatiaLite Writer Feature Type Parameters

To access feature type parameters, click the gear icon on a feature type in the workspace. This opens the Feature Type Parameter Editor.

Tip  To always display the editor in FME Workbench, you can select View > Windows > Parameter Editor.

General

All feature types share similar General parameters, which may include Feature Type Name, Reader or Writer information, and Geometry.

In most Writer Feature Type parameter dialogs, you can also control Dynamic Schema Definitions. Some database formats accept Table or Index Qualifier prefixes on the output table feature type.

Important  These parameters apply only to a selected feature type, not to the entire writer. If a feature type parameter listed here conflicts with a writer-level parameter, then the writer parameter will be ignored and this feature type parameter will be used.

Table: General

This parameter specifies how features will be written into the destination table. Supported feature operations are described below. Note that the described behavior can be dependent on the selected options, as well as the underlying table properties.

Option

Description

If the Row Does Not Exist

If the Row Exists

Insert

The writer appends a new row to a table using input feature attributes.

The writer creates a new row using input feature attributes.

Not always applicable: if the table does not have a unique key or it has an automatically generated unique key, insertion is always possible.

The database cannot violate its key constraints; therefore, errors can occur on row insertion. For example, if there is a unique key and a user specifies the value with the feature, and the feature already exists, then FME Workbench logs an error. This error might be in the form of a rejected feature, or the database may stop processing altogether.

Update

The writer updates existing row(s) in a table using input feature attributes.

A selection method must be specified in the Row Selection group.

The writer rejects the input feature or logs an error if it is unable to continue.

The writer only changes values of the existing row(s) corresponding to the input feature that differ from the input feature.

Upsert

The writer updates the existing row(s) in a table using input feature attributes if the specified conflict arises. If no conflicts arise, the writer appends a new row to a table using input feature attributes.

The writer creates a new row using input feature attributes.

If the specified conflict arises, the writer will change only values of the existing row(s) corresponding to the input feature that differ from the input feature.

If other conflicts arise, the writer will reject the input feature or log an error if it is unable to continue.

Delete

The writer deletes an existing row(s) in a table.

A selection method must be specified in the Row Selection group.

The writer rejects the input feature or logs an error if it is unable to continue.

The writer deletes existing row(s) corresponding to the input feature.

fme_db_
operation

The feature operation will be determined by the attribute fme_db_operation on each input feature.

A selection method must be specified in the Row Selection group.

The value of fme_db_operation will be processed according to the steps below.

Note   The processing steps listed below depend on a format's available Feature Operation options.
  • If the value is null, empty, or missing, it will be treated as an Insert.
  • The value will next be matched to Insert, Update, Upsert, Put, and Delete, case-insensitively.
  • If there is no match, the feature will be rejected.
  • If there is a match, the matched feature operation will be performed on the feature.

Note about earlier FME versions: To use fme_db_operation, you must set Feature Operation to this option. In previous versions of FME, you could set fme_db_operation when the destination feature type was set to Insert, Update, Upsert, or Delete. Doing this now will cause feature rejection.

 The action depends on the operation; however, in general, if nothing is specified, the value is treated as an Insert. The value is treated as an Insert.

Controls how the feature type handles destination tables:

  • Use Existing – Write to an existing table If the destination table does not exist, the translation will fail.
  • Create If Needed – Create the destination table if it does not exist.
  • Drop and Create – (This option is not available in all formats.) Drop the destination table if it exists, and then create it. The writer will drop and re-create the table before writing any features to it. Tables will be overwritten when the first input feature is processed. If no features are sent to a feature type, then the corresponding table will not be overwritten.
  • Truncate Existing – (This option is not available in all formats.) If the destination table does not exist, the translation will fail. Otherwise, delete all rows from the existing table.

This option tells the writer whether to update or skip spatial column(s) when updating features:

  • Yes – The spatial column(s) specified by the user will be updated. IFMENulls will be written as null values, and will replace existing spatial values.
  • No – No spatial columns will be updated.

Feature Operation Option

Row Selection

Insert

Row Selection is ignored.

Update, Upsert, Delete

(Options may differ depending on a format's available Feature Operation options.)

A Row Selection condition needs to be specified for selecting which rows to operate on.

This parameter group offers two methods to construct the selection condition:

Match Columns

The columns specified in the corresponding column picker dialog will be used for matching destination rows. All matching rows will be selected for update, upsert, or delete. If any feature attributes corresponding to the specified match columns contain null or missing values, the feature will be rejected.

Note  This is the only supported method for Upsert feature operation.

WHERE Clause

This parameter opens a WHERE Clause Builder. You can also type a WHERE clause inline, without launching the Builder. It is optional to start the clause with the word WHERE.

The WHERE Clause Builder makes it easy for users to reference feature attribute values, destination table columns, and invoke FME functions. The WHERE clause is first evaluated as an FME expression, before being passed onto the destination database.

If the WHERE clause is incorrect or if its evaluation results in failure, the translation will fail. Otherwise, if the WHERE clause passes FME evaluation but it is SQL invalid, the feature will be rejected or the translation will fail.

For advanced users, conditional FME expressions created through the Conditional Value editor can be used to create WHERE clauses.

Tip  You can set the WHERE Clause to an attribute. This supports workspace migration and existing workflows involving fme_where. (Direct support for fme_where has been deprecated.) To advanced users who are accustomed to using fme_where, if Feature Operation is set to Update, Upsert, Delete, or fme_db_operation, an fme_where attribute that conflicts with Match Columns or WHERE Clause will result in feature rejection.

These parameters take effect when FME creates a table and Geometry is not db_none. These options override writer-level settings of the same name.

Specifies a spatial reference identifier to use when adding a geometry column to a newly-created table.

This parameter is optional and defaults to empty. If this option is empty, the writer coordinate system will be used to try and determine a valid SRID. If the writer coordinate system is also empty, the coordinate system of the first feature will be used. If a valid SRID cannot be determined from any of these sources, an unknown value of 0 will be used.

Alternatively, a specific integer SRID value may be specified. Specified SRID values should correspond to an existing spatial reference identifier value stored in the (SRID) column in the global table.

Note   
  • All geometry within a given table must have the same spatial referencing.
  • If a spatial reference identifier value is not specified, tables will be created with the SRID of the writer coordinate system.
  • If no SRIDs are desired, the value for the SRID field can be set to -1, indicating no spatial reference system.

Specifies a dimension to use when adding a geometry column to a newly-created table:

  • Dimension from First Feature (default) – Files produced will contain geometries with dimension information obtained by the first feature observed by the writer.
  • XY – Files produced will contain 2D coordinate geometry.
  • XYZ – Files produced will contain 3D coordinate geometry.
  • XYM – Files produced will contain 2D (x,y) coordinates, as well as an m (measured value) dimension. m is an extra axis of information not associated with the Cartesian x/y/z space.
  • XYZM – Files produced will contain 3D (x,y,z) coordinate geometry and measures.

Creates a spatial index for the tables produced by the writer. A spatial index can be used to perform geometry-related queries faster.

Default: Yes

Table: Spatial

These parameters take effect when writing features and Geometry is not db_none. These options override writer-level settings of the same name.

Specifies the name of the column to be created that will hold the spatial data when creating a new table.

Determines whether or not lines and polygons will be written SpatiaLite’s compressed geometry format. Selecting Yes will reduce file size.

Default: No