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<p class='location'>Module types</p><div class="sidebar-elems"><div class="block items"><ul><li><a href="#structs">Structs</a></li><li><a href="#enums">Enums</a></li><li><a href="#traits">Traits</a></li><li><a href="#types">Type Definitions</a></li></ul></div><p class='location'><a href='../index.html'>rusqlite</a></p><script>window.sidebarCurrent = {name: 'types', ty: 'mod', relpath: '../'};</script><script defer src="../sidebar-items.js"></script></div>
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<h1 class='fqn'><span class='in-band'>Module <a href='../index.html'>rusqlite</a>::<wbr><a class="mod" href=''>types</a></span><span class='out-of-band'><span id='render-detail'>
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[<span class='inner'>&#x2212;</span>]
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</span><a class='srclink' href='../../src/rusqlite/types/mod.rs.html#1-322' title='goto source code'>[src]</a></span></h1>
<div class='docblock'><p>Traits dealing with SQLite data types.</p>
<p>SQLite uses a <a href="https://www.sqlite.org/datatype3.html">dynamic type system</a>. Implementations of
the <code>ToSql</code> and <code>FromSql</code> traits are provided for the basic types that SQLite provides methods
for:</p>
<ul>
<li>Integers (<code>i32</code> and <code>i64</code>; SQLite uses <code>i64</code> internally, so getting an <code>i32</code> will truncate
if the value is too large or too small).</li>
<li>Reals (<code>f64</code>)</li>
<li>Strings (<code>String</code> and <code>&amp;str</code>)</li>
<li>Blobs (<code>Vec&lt;u8&gt;</code> and <code>&amp;[u8]</code>)</li>
</ul>
<p>Additionally, because it is such a common data type, implementations are provided for
<code>time::Timespec</code> that use a string for storage (using the same format string,
<code>&quot;%Y-%m-%d %H:%M:%S&quot;</code>, as SQLite's builtin
<a href="https://www.sqlite.org/lang_datefunc.html">datetime</a> function. Note that this storage
truncates timespecs to the nearest second. If you want different storage for timespecs, you can
use a newtype. For example, to store timespecs as <code>f64</code>s:</p>
<pre class="rust rust-example-rendered">
<span class="kw">extern</span> <span class="kw">crate</span> <span class="ident">rusqlite</span>;
<span class="kw">extern</span> <span class="kw">crate</span> <span class="ident">time</span>;
<span class="kw">use</span> <span class="ident">rusqlite</span>::<span class="ident">types</span>::{<span class="ident">FromSql</span>, <span class="ident">FromSqlResult</span>, <span class="ident">ValueRef</span>, <span class="ident">ToSql</span>, <span class="ident">ToSqlOutput</span>};
<span class="kw">use</span> <span class="ident">rusqlite</span>::{<span class="prelude-ty">Result</span>};
<span class="kw">pub</span> <span class="kw">struct</span> <span class="ident">TimespecSql</span>(<span class="kw">pub</span> <span class="ident">time</span>::<span class="ident">Timespec</span>);
<span class="kw">impl</span> <span class="ident">FromSql</span> <span class="kw">for</span> <span class="ident">TimespecSql</span> {
<span class="kw">fn</span> <span class="ident">column_result</span>(<span class="ident">value</span>: <span class="ident">ValueRef</span>) <span class="op">-&gt;</span> <span class="ident">FromSqlResult</span><span class="op">&lt;</span><span class="self">Self</span><span class="op">&gt;</span> {
<span class="ident">f64</span>::<span class="ident">column_result</span>(<span class="ident">value</span>).<span class="ident">map</span>(<span class="op">|</span><span class="ident">as_f64</span><span class="op">|</span> {
<span class="ident">TimespecSql</span>(<span class="ident">time</span>::<span class="ident">Timespec</span>{ <span class="ident">sec</span>: <span class="ident">as_f64</span>.<span class="ident">trunc</span>() <span class="kw">as</span> <span class="ident">i64</span>,
<span class="ident">nsec</span>: (<span class="ident">as_f64</span>.<span class="ident">fract</span>() <span class="op">*</span> <span class="number">1.0e9</span>) <span class="kw">as</span> <span class="ident">i32</span> })
})
}
}
<span class="kw">impl</span> <span class="ident">ToSql</span> <span class="kw">for</span> <span class="ident">TimespecSql</span> {
<span class="kw">fn</span> <span class="ident">to_sql</span>(<span class="kw-2">&amp;</span><span class="self">self</span>) <span class="op">-&gt;</span> <span class="prelude-ty">Result</span><span class="op">&lt;</span><span class="ident">ToSqlOutput</span><span class="op">&gt;</span> {
<span class="kw">let</span> <span class="ident">TimespecSql</span>(<span class="ident">ts</span>) <span class="op">=</span> <span class="kw-2">*</span><span class="self">self</span>;
<span class="kw">let</span> <span class="ident">as_f64</span> <span class="op">=</span> <span class="ident">ts</span>.<span class="ident">sec</span> <span class="kw">as</span> <span class="ident">f64</span> <span class="op">+</span> (<span class="ident">ts</span>.<span class="ident">nsec</span> <span class="kw">as</span> <span class="ident">f64</span>) <span class="op">/</span> <span class="number">1.0e9</span>;
<span class="prelude-val">Ok</span>(<span class="ident">as_f64</span>.<span class="ident">into</span>())
}
}
</pre>
<p><code>ToSql</code> and <code>FromSql</code> are also implemented for <code>Option&lt;T&gt;</code> where <code>T</code> implements <code>ToSql</code> or
<code>FromSql</code> for the cases where you want to know if a value was NULL (which gets translated to
<code>None</code>).</p>
</div><h2 id='structs' class='section-header'><a href="#structs">Structs</a></h2>
<table>
<tr class=' module-item'>
<td><a class="struct" href="struct.Null.html"
title='struct rusqlite::types::Null'>Null</a></td>
<td class='docblock-short'>
<p>Empty struct that can be used to fill in a query parameter as <code>NULL</code>.</p>
</td>
</tr></table><h2 id='enums' class='section-header'><a href="#enums">Enums</a></h2>
<table>
<tr class=' module-item'>
<td><a class="enum" href="enum.FromSqlError.html"
title='enum rusqlite::types::FromSqlError'>FromSqlError</a></td>
<td class='docblock-short'>
<p>Enum listing possible errors from <code>FromSql</code> trait.</p>
</td>
</tr>
<tr class=' module-item'>
<td><a class="enum" href="enum.ToSqlOutput.html"
title='enum rusqlite::types::ToSqlOutput'>ToSqlOutput</a></td>
<td class='docblock-short'>
<p><code>ToSqlOutput</code> represents the possible output types for implementors of the <code>ToSql</code> trait.</p>
</td>
</tr>
<tr class=' module-item'>
<td><a class="enum" href="enum.Type.html"
title='enum rusqlite::types::Type'>Type</a></td>
<td class='docblock-short'>
</td>
</tr>
<tr class=' module-item'>
<td><a class="enum" href="enum.Value.html"
title='enum rusqlite::types::Value'>Value</a></td>
<td class='docblock-short'>
<p>Owning <a href="http://sqlite.org/datatype3.html">dynamic type value</a>. Value's type is typically
dictated by SQLite (not by the caller).</p>
</td>
</tr>
<tr class=' module-item'>
<td><a class="enum" href="enum.ValueRef.html"
title='enum rusqlite::types::ValueRef'>ValueRef</a></td>
<td class='docblock-short'>
<p>A non-owning <a href="http://sqlite.org/datatype3.html">dynamic type value</a>. Typically the
memory backing this value is owned by SQLite.</p>
</td>
</tr></table><h2 id='traits' class='section-header'><a href="#traits">Traits</a></h2>
<table>
<tr class=' module-item'>
<td><a class="trait" href="trait.FromSql.html"
title='trait rusqlite::types::FromSql'>FromSql</a></td>
<td class='docblock-short'>
<p>A trait for types that can be created from a SQLite value.</p>
</td>
</tr>
<tr class=' module-item'>
<td><a class="trait" href="trait.ToSql.html"
title='trait rusqlite::types::ToSql'>ToSql</a></td>
<td class='docblock-short'>
<p>A trait for types that can be converted into SQLite values.</p>
</td>
</tr></table><h2 id='types' class='section-header'><a href="#types">Type Definitions</a></h2>
<table>
<tr class=' module-item'>
<td><a class="type" href="type.FromSqlResult.html"
title='type rusqlite::types::FromSqlResult'>FromSqlResult</a></td>
<td class='docblock-short'>
<p>Result type for implementors of the <code>FromSql</code> trait.</p>
</td>
</tr></table></section>
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