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<h1>KVS</h1>
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<main>
<section>
<h3>INTRO</h3>
<p>This module is used to manage different KV backends to your cloud of Erlang apps.
This is an unified abstraction layer to several databases: <b>redis</b>,
<b>mongo</b>, <b>mnesia</b>, <b>riak</b>, <b>aerospike</b>.</p>
<p><blockquote><p><ul>
<li><b><a href="#dir">dir/0</a></b> — table list.</li>
<li><b><a href="#ver">ver/0</a></b> — KVS version.</li>
<li><b><a href="#seq">seq/2</a></b> — generate new sequence id for table.</li>
<li><b><a href="#count">count/1</a></b> — records in table.</li>
<li><b><a href="#put">put/1</a></b> — put record using element 2 as key.</li>
<li><b><a href="#get">get/2</a></b> — get record by key from table.</li>
<li><b><a href="#delete">delete/1</a></b> — delete record from table.</li>
<li><b><a href="#index">index/3</a></b> — index by field and its value.</li>
</ul></p></blockquote></p>
<p>You can change backend by setting application env. This behaves well on </p>
<figure><code>
application:set_env(kvs,dba,store_mnesia).
</code></figure>
</section>
<section>
<h3>RECORDS</h3>
<figure><figcaption>KVS CORE</figcaption><code>
#ok { data= [] :: term() }.
#error { data= [] :: term() }.
#cur { id= [] :: term(),
top= [] :: [] | integer(),
bot= [] :: [] | integer(),
dir= 0 :: 0 | 1,
reader= [] :: [] | tuple(),
writer= [] :: [] | tuple(),
left= 0 :: integer(),
right= 0 :: inetegr() }.
#iter { id= [] :: [] | integer(),
prev= [] :: [] | integer(),
next= [] :: [] | integer()).
</code></figure>
<p><ul>
<li>id — Unique key of the cursor.</li>
</ul></p>
</section>
<section>
<h3>CONFIG</h3>
<p>In sys.config you should specify kvs backend and list of modules
containing <b>metainfo/0</b> exported function.</p>
<figure><code>
[{kvs, [{dba, store_mnesia},
{schema, [kvs]} ]}].
</code></figure>
</section>
<section>
<p>This module may refer to:
<a href="http://erlang.org/doc/man/mnesia.html">mnesia</a></b>,
<a href="kvs_stream.htm"><b>kvs_stream</b></a>.
</p>
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