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Example FFI Usage

The purpose of these crates is to provide an example of how one can use the DataFusion Foreign Function Interface (FFI). See API Docs for detailed usage.

This example is broken into three crates.

• ffi_module_interface is a common library to be shared by both the module to be loaded and the program that will load it. It defines how the module is to be structured.
• ffi_example_table_provider creates a library to exposes the module.
• ffi_module_loader is an example program that loads the module, gets data from it, and displays this data to the user.

Building and running

In order for the program to run successfully, the module to be loaded must be built first. This example expects both the module and the program to be built using the same build mode (debug or release).