Import and export popular data formats from and to dynamic columns

Provide import and export functions for popular data formats like JSON, XML (limited), PHP, ...
for Connector/C and MariaDB Server (which use same code base for dynamic columns)

Tasks:

Dynamic column library (includes MariaDB Server and Connector/C).
1) Add support for arrays with ordinal indexes (currently dynamic columns are limited to use string indexes only)
2) Provide a library for importing/exporting data to and from Dynamic columns.
The following data formats should be supported:

• JSON
• XML (limited to unique keys only)
• PHP,
• ...

MariaDB Server:
3) Provide user defined function (UDF) based on library (task 2) for importing and exporting data

MariaDB Connector/C:
3) Provide a plugin interface based on library (task 2) for importing and exporting data

Examples of usage:

1) MariaDB Server

SET @a:='{"menu": {

  "id": "file",

  "value": "File",

  "popup": {

    "menuitem": [

      {"value": "New", "onclick": "CreateNewDoc()"},

      {"value": "Open", "onclick": "OpenDoc()"},

      {"value": "Close", "onclick": "CloseDoc()"}

    ]

  }

}}';

INSERT INTO my_table (dyncol) VALUES (COLUMN_IMPORT("JSON", @a))

2) Connector/C

 char *json_str='{'menu': {

  'id': 'file',

  'value': 'File',

  'popup': {

    'menuitem': [

      {'value': 'New', 'onclick': 'CreateNewDoc()'},

      {'value': 'Open', 'onclick': 'OpenDoc()'},

      {'value': 'Close', 'onclick': 'CloseDoc()'}

    ]

  }

}}";

rc= mariadb_dyncol_import(dyncol, "json", json_str);

Programming language: C