A function collection plugin will provide an array of Create_item's.

A function collection plugin data will have a structure approximately like this:

struct st_mariadb_function_collection

{

  int m_interface_version;

  HASH m_hash;

  const Native_func_registry *m_elements;

  size_t m_count; // The number of elements in m_elements

};

m_elements will point to a static array of Native_func_registry's, like the one defined in item_create.cc:

static Native_func_registry func_array[] =

{

  { { STRING_WITH_LEN("FUNC1") }, BUILDER(Create_func_func1)},

  { { STRING_WITH_LEN("FUNC2") }, BUILDER(Create_func_func2)},

  { { STRING_WITH_LEN("FUNC3") }, BUILDER(Create_func_func3)},

  { { STRING_WITH_LEN("FUNC4") }, BUILDER(Create_func_func4)},

  { { STRING_WITH_LEN("FUNC5") }, BUILDER(Create_func_func5)},

  ...

};

When initializing a function collection plugin, the server will populate m_hash.
When de-initializing a function collection plugin, the server will free m_hash.

Function collection plugins will allow to:

• Split out optional SQL functions into seperate plugins (e.g. GIS, XML, INET functions)
• Remove conditional compilation from existing server code.
• Provide a better interface (than the existing limited UDF API), which will support:
  • character sets and collations
  • user defined data types