[/
    Copyright (c) 2019-2023 Ruben Perez Hidalgo (rubenperez038 at gmail dot com)
   
    Distributed under the Boost Software License, Version 1.0. (See accompanying
    file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
]

[section:meta Metadata]

In the context of this library, metadata refers to information describing
a column retrieved by the execution of a SQL query. The [reflink metadata] class
contains information about an individual column.

You may access metadata using [refmem results meta] or [refmem execution_state meta].
There is a `metadata` object per column retrieved by the query. The metadata objects are
present even if no row was returned by the query (e.g. a `SELECT` on an empty table).

[reflink connection] objects have an associated [reflink metadata_mode] that describes
how to handle metadata when running a query or a statement:

* If [refmem connection meta_mode] is `metadata_mode::minimal` (the default), the library
  will retain the minimal amout of data required to run the operation. Additional information,
  like column names, won't be retained. Unless you are using metadata explicitly, you should keep
  this default, as it consumes slightly less memory.
* If [refmem connection meta_mode] is `metadata_mode::full`, the library will retain all the information
  provided by the server, including column names.

Only the [reflink metadata] members that are strings (database, table and field names)
are affected by this setting. You may change this setting using [refmem connection set_meta_mode].

For example:

[metadata]

[endsect]
