Working with Large Fields and Container Fields

Most of the formats discussed so far are predominantly text-oriented; that is, either they treat exported data as text, or at the very least they describe its attributes using text-based formats. But FileMaker has extensive capabilities for handling binary data as well, via the container field type. FileMaker can import files in batches, as discussed in the preceding chapter. FileMaker also has tools that allow you to create a batch export of binary files as well. The key to most such exporting operations is the Export Field Contents command, found in the Edit menu. You can manually enter a single field on a FileMaker layout and choose Edit, Export Field Contents, and the contents of that one field will be exported to a file of the appropriate type: a text file for most field types, or the actual file contents of a container field. (For example, exporting from a container field containing a file called hurricanes.dbf will produce exactly the hurricanes.dbf file.) The Export Field Contents option is not available for a container field unless the field contains somethingeither an embedded file or a reference to a file.

When used via the menu, Export Field Contents exports the contents of one selected field from one record. To create something like a batch export of images, it's necessary to write a script that uses the Export Field Contents script step. Scripted exports are a powerful technique that's covered in the next section.