FME considers an Ingres Spatial dataset to be a database containing a collection of relational tables together with their corresponding geometries. The tables must be defined in the mapping file before they can be read. Arbitrary WHERE clauses and joins are fully supported, as well as an entire arbitrary SQL SELECT statement; however, the user then assumes responsibility for the correctness of the statement or clause including quoting where necessary. Support for @SQL and @Relate functions has also been added.
When reading from the Ingres database, each table is considered a feature type in FME and each row of a table at least one feature in FME. In the case of heterogeneous geometry collections, they may become more than one FME feature.
The basic reading process involves opening a connection to the database, querying metadata, and querying data. The data is read using a cursor and rows are fetched to the client machine individually. By default, there is one cursor per input table.
If null geometries are read, they are treated as non-geometry features and the attributes are preserved.
Table and column names are truncated at 256 characters. If duplicate names are produced by truncation, the behavior is undetermined. Please ensure that table names comply with Ingres naming conventions.
Spaces and special characters are permissible in both table and column names. Table and column names are case insensitive and always lowercase.
UNICODE support is enabled either via your databases CHARSET or Unicode char type columns. The client is assumed to have entered data and created tables and columns in the encoding of their operating system.
The user that the client uses to log in with is the schema used for all tables. Specifying schema is not supported.