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<title data-rh="true">Blazing-Fast Memory Mapped RxStorage | RxDB - JavaScript Database</title><meta data-rh="true" name="viewport" content="width=device-width,initial-scale=1"><meta data-rh="true" name="twitter:card" content="summary_large_image"><meta data-rh="true" property="og:image" content="https://rxdb.info/img/rxdb_social_card.png"><meta data-rh="true" name="twitter:image" content="https://rxdb.info/img/rxdb_social_card.png"><meta data-rh="true" property="og:url" content="https://rxdb.info/rx-storage-memory-mapped.html"><meta data-rh="true" property="og:locale" content="en"><meta data-rh="true" name="docusaurus_locale" content="en"><meta data-rh="true" name="docsearch:language" content="en"><meta data-rh="true" name="docusaurus_version" content="current"><meta data-rh="true" name="docusaurus_tag" content="docs-default-current"><meta data-rh="true" name="docsearch:version" content="current"><meta data-rh="true" name="docsearch:docusaurus_tag" content="docs-default-current"><meta data-rh="true" property="og:title" content="Blazing-Fast Memory Mapped RxStorage | RxDB - JavaScript Database"><meta data-rh="true" name="description" content="Boost your app's performance with Memory Mapped RxStorage. Query and write in-memory while seamlessly persisting data to your chosen storage."><meta data-rh="true" property="og:description" content="Boost your app's performance with Memory Mapped RxStorage. Query and write in-memory while seamlessly persisting data to your chosen storage."><link data-rh="true" rel="icon" href="/img/favicon.ico"><link data-rh="true" rel="canonical" href="https://rxdb.info/rx-storage-memory-mapped.html"><link data-rh="true" rel="alternate" href="https://rxdb.info/rx-storage-memory-mapped.html" hreflang="en"><link data-rh="true" rel="alternate" href="https://rxdb.info/rx-storage-memory-mapped.html" hreflang="x-default"><link rel="preconnect" href="https://www.google-analytics.com">
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padding-bottom--lg"><div class="row"><div class="col docItemCol_VOVn"><div class="docItemContainer_Djhp"><article><nav class="theme-doc-breadcrumbs breadcrumbsContainer_Z_bl" aria-label="Breadcrumbs"><ul class="breadcrumbs" itemscope="" itemtype="https://schema.org/BreadcrumbList"><li class="breadcrumbs__item"><a aria-label="Home page" class="breadcrumbs__link" href="/"><svg viewBox="0 0 24 24" class="breadcrumbHomeIcon_YNFT"><path d="M10 19v-5h4v5c0 .55.45 1 1 1h3c.55 0 1-.45 1-1v-7h1.7c.46 0 .68-.57.33-.87L12.67 3.6c-.38-.34-.96-.34-1.34 0l-8.36 7.53c-.34.3-.13.87.33.87H5v7c0 .55.45 1 1 1h3c.55 0 1-.45 1-1z" fill="currentColor"></path></svg></a></li><li class="breadcrumbs__item"><span class="breadcrumbs__link">Storage Wrappers</span><meta itemprop="position" content="1"></li><li itemscope="" itemprop="itemListElement" itemtype="https://schema.org/ListItem" class="breadcrumbs__item breadcrumbs__item--active"><span class="breadcrumbs__link" itemprop="name">Memory Mapped RxStorage 👑</span><meta itemprop="position" content="2"></li></ul></nav><div class="tocCollapsible_ETCw theme-doc-toc-mobile tocMobile_ITEo"><button type="button" class="clean-btn tocCollapsibleButton_TO0P">On this page</button></div><div class="theme-doc-markdown markdown"><header><h1>Memory Mapped RxStorage</h1></header>
<p>The memory mapped <a href="/rx-storage.html">RxStorage</a> is a wrapper around any other RxStorage. The wrapper creates an in-memory storage that is used for query and write operations. This memory instance is kept persistent with a given underlying storage.</p>
<h2 class="anchor anchorWithStickyNavbar_LWe7" id="pros">Pros<a href="#pros" class="hash-link" aria-label="Direct link to Pros" title="Direct link to Pros"></a></h2>
<ul>
<li>Improves read/write performance because these operations run against the in-memory storage.</li>
<li>Decreases initial page load because it load all data in a single bulk request. It even detects if the database is used for the first time and then it does not have to await the creation of the persistent storage.</li>
<li>Can store encrypted data on disc while still being able to run queries on the non-encrypted in-memory state.</li>
</ul>
<h2 class="anchor anchorWithStickyNavbar_LWe7" id="cons">Cons<a href="#cons" class="hash-link" aria-label="Direct link to Cons" title="Direct link to Cons"></a></h2>
<ul>
<li>It does not support attachments because storing big attachments data in-memory should not be done.</li>
<li>When the JavaScript process is killed ungracefully like when the browser crashes or the power of the PC is terminated, it might happen that some memory writes are not persisted to the parent storage. This can be prevented with the <code>awaitWritePersistence</code> flag.</li>
<li>The memory-mapped storage can only be used if all data fits into the memory of the JavaScript process. This is normally not a problem because a browser has much memory these days and plain JSON document data is not that big.</li>
<li>Because it has to await an initial data loading from the parent storage into the memory, initial page load time can increase when much data is already stored. This is likely not a problem when you store less than <code>10k</code> documents.</li>
<li>The <code>memory-mapped</code> storage is part of <a href="/premium/">RxDB Premium 👑</a>. It is not part of the default RxDB core module.</li>
</ul>
<h2 class="anchor anchorWithStickyNavbar_LWe7" id="using-the-memory-mapped-rxstorage">Using the Memory-Mapped RxStorage<a href="#using-the-memory-mapped-rxstorage" class="hash-link" aria-label="Direct link to Using the Memory-Mapped RxStorage" title="Direct link to Using the Memory-Mapped RxStorage"></a></h2>
<div class="language-ts codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-ts codeBlock_bY9V thin-scrollbar" style="color:#F8F8F2;background-color:#282A36"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">import</span><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> getRxStorageIndexedDB</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token punctuation" style="color:rgb(248, 248, 242)">}</span><span class="token plain"> </span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">from</span><span class="token plain"> </span><span class="token string" style="color:rgb(255, 121, 198)">'rxdb-premium/plugins/storage-indexeddb'</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">import</span><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> getMemoryMappedRxStorage</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token punctuation" style="color:rgb(248, 248, 242)">}</span><span class="token plain"> </span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">from</span><span class="token plain"> </span><span class="token string" style="color:rgb(255, 121, 198)">'rxdb-premium/plugins/storage-memory-mapped'</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token doc-comment comment" style="color:rgb(98, 114, 164)">/**</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * Here we use the IndexedDB RxStorage as persistence storage.</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * Any other RxStorage can also be used.</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> */</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">const</span><span class="token plain"> parentStorage </span><span class="token operator">=</span><span class="token plain"> </span><span class="token function" style="color:rgb(80, 250, 123)">getRxStorageIndexedDB</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token comment" style="color:rgb(98, 114, 164)">// wrap the persistent storage with the memory-mapped storage.</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">const</span><span class="token plain"> storage </span><span class="token operator">=</span><span class="token plain"> </span><span class="token function" style="color:rgb(80, 250, 123)">getMemoryMappedRxStorage</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> storage</span><span class="token operator">:</span><span class="token plain"> parentStorage</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token punctuation" style="color:rgb(248, 248, 242)">}</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token comment" style="color:rgb(98, 114, 164)">// create the RxDatabase like you would do with any other RxStorage</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">const</span><span class="token plain"> db </span><span class="token operator">=</span><span class="token plain"> </span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">await</span><span class="token plain"> </span><span class="token function" style="color:rgb(80, 250, 123)">createRxDatabase</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> name</span><span class="token operator">:</span><span class="token plain"> 'myDatabase</span><span class="token punctuation" style="color:rgb(248, 248, 242)">,</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> storage</span><span class="token punctuation" style="color:rgb(248, 248, 242)">,</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token punctuation" style="color:rgb(248, 248, 242)">}</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token doc-comment comment" style="color:rgb(98, 114, 164)">/** ... **/</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg viewBox="0 0 24 24" class="copyButtonIcon_y97N"><path fill="currentColor" d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg viewBox="0 0 24 24" class="copyButtonSuccessIcon_LjdS"><path fill="currentColor" d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div>
<h2 class="anchor anchorWithStickyNavbar_LWe7" id="multi-tab-support">Multi-Tab Support<a href="#multi-tab-support" class="hash-link" aria-label="Direct link to Multi-Tab Support" title="Direct link to Multi-Tab Support"></a></h2>
<p>By how the memory-mapped storage works, it is not possible to have the same storage open in multiple JavaScript processes. So when you use this in a browser application, you can not open multiple databases when the app is used in multiple browser tabs.
To solve this, use the <a href="/rx-storage-shared-worker.html">SharedWorker Plugin</a> so that the memory-mapped storage runs inside of a SharedWorker exactly once and is then reused for all browser tabs.</p>
<p>If you have a single JavaScript process, like in a React Native app, you do not have to care about this and can just use the memory-mapped storage in the main process.</p>
<h2 class="anchor anchorWithStickyNavbar_LWe7" id="encryption-of-the-persistend-data">Encryption of the persistend data<a href="#encryption-of-the-persistend-data" class="hash-link" aria-label="Direct link to Encryption of the persistend data" title="Direct link to Encryption of the persistend data"></a></h2>
<p>Normally RxDB is not capable of running queries on encrypted fields. But when you use the memory-mapped RxStorage, you can store the document data encrypted on disc, while being able to run queries on the not encrypted in-memory state. Make sure you use the encryption storage wrapper around the persistend storage, <strong>NOT</strong> around the memory-mapped storage as a whole.</p>
<div class="language-ts codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-ts codeBlock_bY9V thin-scrollbar" style="color:#F8F8F2;background-color:#282A36"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">import</span><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> getRxStorageIndexedDB</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token punctuation" style="color:rgb(248, 248, 242)">}</span><span class="token plain"> </span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">from</span><span class="token plain"> </span><span class="token string" style="color:rgb(255, 121, 198)">'rxdb-premium/plugins/storage-indexeddb'</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">import</span><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> getMemoryMappedRxStorage</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token punctuation" style="color:rgb(248, 248, 242)">}</span><span class="token plain"> </span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">from</span><span class="token plain"> </span><span class="token string" style="color:rgb(255, 121, 198)">'rxdb-premium/plugins/storage-memory-mapped'</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">import</span><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">{</span><span class="token plain"> wrappedKeyEncryptionWebCryptoStorage </span><span class="token punctuation" style="color:rgb(248, 248, 242)">}</span><span class="token plain"> </span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">from</span><span class="token plain"> </span><span class="token string" style="color:rgb(255, 121, 198)">'rxdb-premium/plugins/encryption-web-crypto'</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">const</span><span class="token plain"> storage </span><span class="token operator">=</span><span class="token plain"> </span><span class="token function" style="color:rgb(80, 250, 123)">getMemoryMappedRxStorage</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> storage</span><span class="token operator">:</span><span class="token plain"> </span><span class="token function" style="color:rgb(80, 250, 123)">wrappedKeyEncryptionWebCryptoStorage</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> storage</span><span class="token operator">:</span><span class="token plain"> </span><span class="token function" style="color:rgb(80, 250, 123)">getRxStorageIndexedDB</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">}</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token punctuation" style="color:rgb(248, 248, 242)">}</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">const</span><span class="token plain"> db </span><span class="token operator">=</span><span class="token plain"> </span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">await</span><span class="token plain"> </span><span class="token function" style="color:rgb(80, 250, 123)">createRxDatabase</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> name</span><span class="token operator">:</span><span class="token plain"> 'myDatabase</span><span class="token punctuation" style="color:rgb(248, 248, 242)">,</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> storage</span><span class="token punctuation" style="color:rgb(248, 248, 242)">,</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token punctuation" style="color:rgb(248, 248, 242)">}</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token doc-comment comment" style="color:rgb(98, 114, 164)">/** ... **/</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg viewBox="0 0 24 24" class="copyButtonIcon_y97N"><path fill="currentColor" d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg viewBox="0 0 24 24" class="copyButtonSuccessIcon_LjdS"><path fill="currentColor" d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div>
<h2 class="anchor anchorWithStickyNavbar_LWe7" id="await-write-persistence">Await Write Persistence<a href="#await-write-persistence" class="hash-link" aria-label="Direct link to Await Write Persistence" title="Direct link to Await Write Persistence"></a></h2>
<p>Running operations on the memory-mapped storage by default returns directly when the operation has run on the in-memory state and then persist changes in the background.
Sometimes you might want to ensure write operations is persisted, you can do this by setting <code>awaitWritePersistence: true</code>.</p>
<div class="language-ts codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-ts codeBlock_bY9V thin-scrollbar" style="color:#F8F8F2;background-color:#282A36"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">const</span><span class="token plain"> storage </span><span class="token operator">=</span><span class="token plain"> </span><span class="token function" style="color:rgb(80, 250, 123)">getMemoryMappedRxStorage</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> awaitWritePersistence</span><span class="token operator">:</span><span class="token plain"> </span><span class="token boolean">true</span><span class="token punctuation" style="color:rgb(248, 248, 242)">,</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> storage</span><span class="token operator">:</span><span class="token plain"> </span><span class="token function" style="color:rgb(80, 250, 123)">getRxStorageIndexedDB</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token punctuation" style="color:rgb(248, 248, 242)">}</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg viewBox="0 0 24 24" class="copyButtonIcon_y97N"><path fill="currentColor" d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg viewBox="0 0 24 24" class="copyButtonSuccessIcon_LjdS"><path fill="currentColor" d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div></div></article><nav class="pagination-nav docusaurus-mt-lg" aria-label="Docs pages"><a class="pagination-nav__link pagination-nav__link--prev" href="/rx-storage-shared-worker.html"><div class="pagination-nav__sublabel">Previous</div><div class="pagination-nav__label">SharedWorker RxStorage 👑</div></a><a class="pagination-nav__link pagination-nav__link--next" href="/rx-storage-sharding.html"><div class="pagination-nav__sublabel">Next</div><div class="pagination-nav__label">Sharding 👑</div></a></nav></div></div><div class="col col--3"><div class="tableOfContents_bqdL thin-scrollbar theme-doc-toc-desktop"><ul class="table-of-contents table-of-contents__left-border"><li><a href="#pros" class="table-of-contents__link toc-highlight">Pros</a></li><li><a href="#cons" class="table-of-contents__link toc-highlight">Cons</a></li><li><a href="#using-the-memory-mapped-rxstorage" class="table-of-contents__link toc-highlight">Using the Memory-Mapped RxStorage</a></li><li><a href="#multi-tab-support" class="table-of-contents__link toc-highlight">Multi-Tab Support</a></li><li><a href="#encryption-of-the-persistend-data" class="table-of-contents__link toc-highlight">Encryption of the persistend data</a></li><li><a href="#await-write-persistence" class="table-of-contents__link toc-highlight">Await Write Persistence</a></li></ul></div></div></div></div></main></div></div></div><div class="block 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