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+</ul>
+<p class="caption"><span class="caption-text">Data Storage</span></p>
+<ul class="current">
+<li class="toctree-l1"><a class="reference internal" href="data-store-dbms.html">The Usergrid Data Store</a></li>
+<li class="toctree-l1 current"><a class="current reference internal" href="">Data Store Best Practices</a><ul>
+<li class="toctree-l2"><a class="reference internal" href="#put-your-data-in-as-you-ll-want-to-get-it-out">Put your data in as you’ll want to get it out</a></li>
+<li class="toctree-l2"><a class="reference internal" href="#best-practice-denormalize-for-pre-computed-query-results">Best practice: Denormalize for pre-computed query results</a><ul>
+<li class="toctree-l3"><a class="reference internal" href="#getting-review-data-the-relational-way">Getting review data the relational way</a></li>
+<li class="toctree-l3"><a class="reference internal" href="#using-a-denormalized-model-to-store-then-retrieve-data">Using a denormalized model to store (then retrieve) data</a></li>
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+<p class="caption"><span class="caption-text">Data Queries</span></p>
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+<li class="toctree-l1"><a class="reference internal" href="../data-queries/querying-your-data.html">Querying your data</a></li>
+<li class="toctree-l1"><a class="reference internal" href="../data-queries/query-parameters.html">Query parameters & clauses</a></li>
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+<p class="caption"><span class="caption-text">Entity Connections</span></p>
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+<li class="toctree-l1"><a class="reference internal" href="../security-and-auth/securing-your-app.html">Security best practices</a></li>
+</ul>
+<p class="caption"><span class="caption-text">User Management & Social Graph</span></p>
+<ul>
+<li class="toctree-l1"><a class="reference internal" href="../user-management/user-management.html">User management & social graph</a></li>
+<li class="toctree-l1"><a class="reference internal" href="../user-management/working-user-data.html">Working with User Data</a></li>
+<li class="toctree-l1"><a class="reference internal" href="../user-management/group.html">Working with group data</a></li>
+<li class="toctree-l1"><a class="reference internal" href="../user-management/activity.html">Activity</a></li>
+<li class="toctree-l1"><a class="reference internal" href="../user-management/user-connections.html">Social Graph Connections</a></li>
+<li class="toctree-l1"><a class="reference internal" href="../user-management/user-connections.html#creating-other-connections">Creating other connections</a></li>
+<li class="toctree-l1"><a class="reference internal" href="../user-management/messagee-example.html">App Example - Messagee</a></li>
+</ul>
+<p class="caption"><span class="caption-text">Geo-location</span></p>
+<ul>
+<li class="toctree-l1"><a class="reference internal" href="../geolocation/geolocation.html">Geolocating your Entities</a></li>
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+<p class="caption"><span class="caption-text">Assets & Files</span></p>
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+<li class="toctree-l1"><a class="reference internal" href="../asset-and-files/uploading-assets.html">Uploading assets</a></li>
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+<p class="caption"><span class="caption-text">Counters & Events</span></p>
+<ul>
+<li class="toctree-l1"><a class="reference internal" href="../counters-and-events/events-and-counters.html">Counters & events</a></li>
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+<li class="toctree-l1"><a class="reference internal" href="../counters-and-events/creating-and-incrementing-counters.html#decrementing-resetting-counters">Decrementing/resetting counters</a></li>
+<li class="toctree-l1"><a class="reference internal" href="../counters-and-events/creating-and-incrementing-counters.html#using-counters-hierarchically">Using counters hierarchically</a></li>
+<li class="toctree-l1"><a class="reference internal" href="../counters-and-events/retrieving-counters.html">Retrieving counters</a></li>
+</ul>
+<p class="caption"><span class="caption-text">Organizations & Applications</span></p>
+<ul>
+<li class="toctree-l1"><a class="reference internal" href="../orgs-and-apps/managing.html">Organization & application management</a></li>
+<li class="toctree-l1"><a class="reference internal" href="../orgs-and-apps/organization.html">Organization</a></li>
+<li class="toctree-l1"><a class="reference internal" href="../orgs-and-apps/application.html">Application</a></li>
+</ul>
+<p class="caption"><span class="caption-text">API Reference</span></p>
+<ul>
+<li class="toctree-l1"><a class="reference internal" href="../rest-endpoints/api-docs.html">Methods</a></li>
+<li class="toctree-l1"><a class="reference internal" href="../rest-endpoints/api-docs.html#models">Models</a></li>
+</ul>
+<p class="caption"><span class="caption-text">Client SDKs</span></p>
+<ul>
+<li class="toctree-l1"><a class="reference internal" href="../sdks/tbd.html">COMING SOON...</a></li>
+</ul>
+<p class="caption"><span class="caption-text">Installing the Stack</span></p>
+<ul>
+<li class="toctree-l1"><a class="reference internal" href="../installation/ug1-deploy-to-tomcat.html">Usegrid 1: Deploying to Tomcat</a></li>
+<li class="toctree-l1"><a class="reference internal" href="../installation/ug1-launcher-quick-start.html">Usegrid 1: Launcher Quick-start</a></li>
+<li class="toctree-l1"><a class="reference internal" href="../installation/ug2-deploy-to-tomcat.html">Usergrid 2: Deploy to Tomcat</a></li>
+</ul>
+<p class="caption"><span class="caption-text">More about Usergrid</span></p>
+<ul>
+<li class="toctree-l1"><a class="reference internal" href="../reference/presos-and-videos.html">Presentations & Videos</a></li>
+<li class="toctree-l1"><a class="reference internal" href="../reference/contribute-code.html">How to Contribute Code & Docs</a></li>
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+ <div class="section" id="data-store-best-practices">
+<h1>Data Store Best Practices<a class="headerlink" href="#data-store-best-practices" title="Permalink to this headline">¶</a></h1>
+<p>The Usergrid data store is backed by Cassandra, an open source
+distributed DBMS. Cassandra is specifically designed to support
+applications that need flexibility and high scalability, particularly
+web and mobile applications. To get the most out of your Usergrid
+application, you should optimize your data access with this kind of
+database in mind.</p>
+<div class="section" id="put-your-data-in-as-you-ll-want-to-get-it-out">
+<h2>Put your data in as you’ll want to get it out<a class="headerlink" href="#put-your-data-in-as-you-ll-want-to-get-it-out" title="Permalink to this headline">¶</a></h2>
+<p>The best practices described here are all related to the theme of
+putting your data in the way you’ll want to get it out. You’ll model
+your data with your likely read requests in mind rather than by modeling
+around the structure of the data itself (as you might with a relational
+database). In many cases, you can avoid using queries that are
+inefficient for this kind of database.</p>
+<p>You can use the following techniques to optimize data store access:</p>
+<ul class="simple">
+<li><strong>Denormalize and duplicate</strong>. By creating a data model that
+strategically denormalizes and duplicates data, you can avoid costly
+queries. In other words, you model the data so that all of the data
+for a given request is all in one place rather than scattered in a
+way that a query must account for.</li>
+<li><strong>Create direct paths to the data you’ll want</strong>. You can optimize
+your app’s performance by connecting entities your code retrieves
+most often. With connections, you can avoid some queries that might
+add complexity and reduce performance.</li>
+</ul>
+</div>
+<div class="section" id="best-practice-denormalize-for-pre-computed-query-results">
+<h2>Best practice: Denormalize for pre-computed query results<a class="headerlink" href="#best-practice-denormalize-for-pre-computed-query-results" title="Permalink to this headline">¶</a></h2>
+<p>If you’re familiar with designing relational databases, you’re probably
+used to normalizing the structure of your data as much as possible. When
+normalizing an RDBMS data model, you minimize redundancy by ensuring
+that a column from one table is duplicated only once in any other table,
+and only when necessary to create primary/secondary key relationships.
+You then retrieve data that spans tables by joining them with an SQL
+query.</p>
+<p>In contrast, with the Usergrid data store you’ll get better performance
+by strategically denormalizing and duplicating data. When you
+denormalize, you combine data from what might (in a relational model)
+have been separate tables. When duplicating, you intentionally maintain
+copies of certain entity properties across multiple entities. By
+denormalizing and duplicating, you can collect the results of requests
+into a single entity rather than relying on a query.</p>
+<p>Part of designing your data model should include identifying the queries
+your client will make. Then in your data model design, you capture the
+results of those queries in advance by writing that data into entities
+of one collection you can read from later.</p>
+<div class="section" id="getting-review-data-the-relational-way">
+<h3>Getting review data the relational way<a class="headerlink" href="#getting-review-data-the-relational-way" title="Permalink to this headline">¶</a></h3>
+<p>For example, take a closer look at the relational case through a product
+database. Imagine you want to present a list of all reviews for a
+product. When a user chooses a review from the list, you’ll show them a
+view that includes the review’s title, body, and rating; the product it
+describes; and who wrote the review. That way, your user will be able to
+click through to more information about the product or reviewing user.</p>
+<p>In a relational database, you’d likely have separate tables for the
+review-specific information and a rating; for the product; and for the
+user. Your reviews table would include secondary keys with which to join
+reviews to the users and products tables. Maybe something like this:</p>
+<img alt="../_images/reviews.png" src="../_images/reviews.png" />
+<p>To get the data you need, your query might look like the SQL query
+below. By getting UUIDs for the user and product into your client code,
+you’re able to give the user a way to get user and product information
+from the review.</p>
+<div class="highlight-python"><div class="highlight"><pre>SELECT review.title, review.body, review.rating, review.uuid,
+ user.name, user.uuid, product.name, product.uuid
+ FROM reviews
+ INNER JOIN users
+ ON users.uuid = reviews.authorId
+ INNER JOIN products
+ ON products.uuid = reviews.productId
+ WHERE reviews.uuid = <uuid_for_selected_review>
+</pre></div>
+</div>
+<p>But due to Cassandra’s distributed, high-scale design, a join such as
+this wouldn’t work. So in the Usergrid, you’d get the data by first
+storing it all in one place.</p>
+</div>
+<div class="section" id="using-a-denormalized-model-to-store-then-retrieve-data">
+<h3>Using a denormalized model to store (then retrieve) data<a class="headerlink" href="#using-a-denormalized-model-to-store-then-retrieve-data" title="Permalink to this headline">¶</a></h3>
+<p>In the Usergrid, a more efficient way to get the same result would start
+by including related user and product data with the review data. This
+would give you a single place to get all the data you’ll show.</p>
+<p>The following shows how that model might look as entities in the
+Usergrid. (The users and products entities are included here to remind
+you that they exist, but they aren’t actually used in this
+denormalization example.)</p>
+<img alt="../_images/reviews2.png" src="../_images/reviews2.png" />
+<p>This use case assumes that your user and product data are already in the
+data store. In the following API request code, you’re just adding a new
+review written by a user about a particular product. The JSON body is
+your new review entity (the JSON here is non-entitized to make it
+readable).</p>
+<div class="highlight-python"><div class="highlight"><pre>POST https://api.usergrid.com/my_org/my_app/reviews -d {
+ "title" : "Tempted to climb in myself.",
+ "body" : "I mean, who doesn't love a bouncy castle? The kids love it!",
+ "rating" : 3,
+ "authorName" : "Jennie",
+ "authorUUID" : <author_uuid>,
+ "authorImage" : "http://<path_to_image>.png",
+ "productUUID" : <product_uuid>,
+ "productImage" : "http://<path_to_image>.jpg",
+ "productName" : "Magic Castle Bounce House Inflatable Bouncer"
+}
+</pre></div>
+</div>
+<p>Notice that you’re adding user and product data (which your client code
+would have at hand when the user posts the review) when you’re adding
+the review-specific data.</p>
+<p>Retrieving all the data from one place You’d get the review, including
+the subset of product and user data you need right away, by making one
+API call such as the following (note there’s no SQL-like query string
+needed):</p>
+<div class="highlight-python"><div class="highlight"><pre>GET http://api.usergrid.com/my_org/my_app/reviews/<review_uuid>
+</pre></div>
+</div>
+<p>Your result might look like this. The highlighted lines show data you’d
+present to the user.</p>
+<div class="highlight-python"><div class="highlight"><pre><span class="p">{</span>
+ <span class="s">"action"</span> <span class="p">:</span> <span class="s">"get"</span><span class="p">,</span>
+ <span class="s">"application"</span> <span class="p">:</span> <span class="s">"<app_uuid>"</span><span class="p">,</span>
+ <span class="s">"params"</span> <span class="p">:</span> <span class="p">{</span> <span class="p">},</span>
+ <span class="s">"path"</span> <span class="p">:</span> <span class="s">"/reviews"</span><span class="p">,</span>
+ <span class="s">"uri"</span> <span class="p">:</span> <span class="s">"https://api.usergrid.com/my_org/my_app/reviews"</span><span class="p">,</span>
+ <span class="s">"entities"</span> <span class="p">:</span> <span class="p">[</span> <span class="p">{</span>
+ <span class="s">"uuid"</span> <span class="p">:</span> <span class="s">"<review_uuid>"</span><span class="p">,</span>
+ <span class="s">"type"</span> <span class="p">:</span> <span class="s">"review"</span><span class="p">,</span>
+ <span class="s">"created"</span> <span class="p">:</span> <span class="mi">1395410364673</span><span class="p">,</span>
+ <span class="s">"modified"</span> <span class="p">:</span> <span class="mi">1395410364673</span><span class="p">,</span>
+ <span class="s">"authorName"</span> <span class="p">:</span> <span class="s">"Jennie"</span><span class="p">,</span>
+ <span class="s">"authorImage"</span> <span class="p">:</span> <span class="s">"<path_to_image>.png"</span><span class="p">,</span>
+ <span class="s">"authorUUID"</span> <span class="p">:</span> <span class="s">"<author_uuid>"</span><span class="p">,</span>
+ <span class="s">"body"</span> <span class="p">:</span> <span class="s">"I mean, who doesn't love a bouncy castle? The kids love it!"</span><span class="p">,</span>
+ <span class="s">"metadata"</span> <span class="p">:</span> <span class="p">{</span>
+ <span class="s">"path"</span> <span class="p">:</span> <span class="s">"/reviews/<review_uuid>"</span>
+ <span class="p">},</span>
+ <span class="s">"productImage"</span> <span class="p">:</span> <span class="s">"http://<path_to_image>.jpg"</span><span class="p">,</span>
+ <span class="s">"productName"</span> <span class="p">:</span> <span class="s">"Magic Castle Bounce House Inflatable Bouncer"</span><span class="p">,</span>
+ <span class="s">"productUUID"</span> <span class="p">:</span> <span class="s">"<product_uuid>"</span><span class="p">,</span>
+ <span class="s">"rating"</span> <span class="p">:</span> <span class="mi">3</span><span class="p">,</span>
+ <span class="s">"title"</span> <span class="p">:</span> <span class="s">"Tempted to climb in myself."</span>
+ <span class="p">}</span> <span class="p">],</span>
+ <span class="s">"timestamp"</span> <span class="p">:</span> <span class="mi">1395764951934</span><span class="p">,</span>
+ <span class="s">"duration"</span> <span class="p">:</span> <span class="mi">16</span><span class="p">,</span>
+ <span class="s">"organization"</span> <span class="p">:</span> <span class="s">"my_org"</span><span class="p">,</span>
+ <span class="s">"applicationName"</span> <span class="p">:</span> <span class="s">"my_app"</span>
+<span class="p">}</span>
+</pre></div>
+</div>
+<p>This gives you, in one request, all the review information you’d planned
+on presenting to your app’s users for a single view. Your client code
+could retrieve the review entity in the result, along with the product
+and user data, then present it all as a review.</p>
+<p>Best practice: Connect entities to simplify scoped requests Another way
+to streamline your requests is to connect entities by using the built-in
+connections feature. In a sense, a connection can replace the WHERE
+clause of a query you might have written.</p>
+<p>Getting back to the review example, imagine you want to retrieve all of
+the reviews written by a particular user. In the relational example, you
+might have an SQL query such as this:</p>
+<div class="highlight-python"><div class="highlight"><pre>SELECT * FROM reviews WHERE authorId = <user_uuid>;
+</pre></div>
+</div>
+<p>Even in the Usergrid, you could use a similar syntax in a query string
+appended to an API path. Working from the review entity model in the
+preceding example, that might look like this (though yours would likely
+entitize the spaces):</p>
+<div class="highlight-python"><div class="highlight"><pre>GET http://api.usergrid.com/my_org/my_app/reviews?ql=select * where
+ authorUUID=<user_uuid>
+</pre></div>
+</div>
+<p>But if this is an API call you’re going to be making often, there’s a
+better way. Instead, create a connection between the review and the user
+when your code creates the review. You can connect entities with a verb
+that describes their relationship to one another.</p>
+<p>The following creates Jennie’s review and at the same time connects her
+as the person who “wrote” it. (For easier reading, this example contains
+spaces you wouldn’t be able to include.)</p>
+<div class="highlight-python"><div class="highlight"><pre>POST http://api.usergrid.com/my_org/my_app/users/jennie/wrote/reviews {
+ "title" : "Tempted to climb in myself.",
+ "body" : "I mean, who doesn't love a bouncy castle? The kids love it!",
+ "rating" : 3,
+ "authorName" : "Jennie",
+ "authorImage" : "http://<path_to_image>.png",
+ "productName" : "Magic Castle Bounce House Inflatable Bouncer",
+ "productImage" : "http://<path_to_image>.jpg"
+}
+</pre></div>
+</div>
+<p>When reading the data, you’d retrieve all of the reviews Jennie has
+written with a URL that’s nearly identical, minus the JSON:</p>
+<div class="highlight-python"><div class="highlight"><pre>GET http://api.usergrid.com/my_org/my_app/users/jennie/wrote/reviews
+</pre></div>
+</div>
+<p>Your request result would look something like the following. Here, the
+entities array returned contains the reviews you connected with Jennie
+(though there’s only one in this example). The connection-specific
+metadata is highlighted.</p>
+<div class="highlight-python"><div class="highlight"><pre><span class="p">{</span>
+ <span class="s">"action"</span> <span class="p">:</span> <span class="s">"get"</span><span class="p">,</span>
+ <span class="s">"application"</span> <span class="p">:</span> <span class="s">"<app_uuid>"</span><span class="p">,</span>
+ <span class="s">"params"</span> <span class="p">:</span> <span class="p">{</span> <span class="p">},</span>
+ <span class="s">"path"</span> <span class="p">:</span> <span class="s">"/users/<user_uuid>/wrote"</span><span class="p">,</span>
+ <span class="s">"uri"</span> <span class="p">:</span> <span class="s">"https://api.usergrid.com/my_org/my_app/users/<user_uuid>/wrote"</span><span class="p">,</span>
+ <span class="s">"entities"</span> <span class="p">:</span> <span class="p">[</span> <span class="p">{</span>
+ <span class="s">"uuid"</span> <span class="p">:</span> <span class="s">"<review_uuid>"</span><span class="p">,</span>
+ <span class="s">"type"</span> <span class="p">:</span> <span class="s">"review"</span><span class="p">,</span>
+ <span class="s">"created"</span> <span class="p">:</span> <span class="mi">1395410364673</span><span class="p">,</span>
+ <span class="s">"modified"</span> <span class="p">:</span> <span class="mi">1395410364673</span><span class="p">,</span>
+ <span class="s">"authorName"</span> <span class="p">:</span> <span class="s">"Jennie"</span><span class="p">,</span>
+ <span class="s">"authorImage"</span> <span class="p">:</span> <span class="s">"http://<path_to_image>.png"</span><span class="p">,</span>
+ <span class="s">"authorUUID"</span> <span class="p">:</span> <span class="s">"<user_uuid>"</span><span class="p">,</span>
+ <span class="s">"body"</span> <span class="p">:</span> <span class="s">"I mean, who doesn't love a bouncy castle? Kids love it!"</span><span class="p">,</span>
+ <span class="s">"metadata"</span> <span class="p">:</span> <span class="p">{</span>
+ <span class="s">"connecting"</span> <span class="p">:</span> <span class="p">{</span>
+ <span class="s">"wrote"</span> <span class="p">:</span> <span class="s">"/users/<user_uuid>/wrote/<review_uuid>/connecting/wrote"</span>
+ <span class="p">},</span>
+ <span class="s">"path"</span> <span class="p">:</span> <span class="s">"/users/<user_uuid>/wrote/<review_uuid>"</span><span class="p">,</span>
+ <span class="p">},</span>
+ <span class="s">"productImage"</span> <span class="p">:</span> <span class="s">"http://<path_to_image>.jpg"</span><span class="p">,</span>
+ <span class="s">"productName"</span> <span class="p">:</span> <span class="s">"Magic Castle Bounce House Inflatable Bouncer"</span><span class="p">,</span>
+ <span class="s">"productUUID"</span> <span class="p">:</span> <span class="s">"<product_uuid>"</span><span class="p">,</span>
+ <span class="s">"rating"</span> <span class="p">:</span> <span class="mi">3</span><span class="p">,</span>
+ <span class="s">"title"</span> <span class="p">:</span> <span class="s">"Tempted to climb in myself."</span>
+ <span class="p">}</span> <span class="p">],</span>
+ <span class="s">"timestamp"</span> <span class="p">:</span> <span class="mi">1395777037697</span><span class="p">,</span>
+ <span class="s">"duration"</span> <span class="p">:</span> <span class="mi">19</span><span class="p">,</span>
+ <span class="s">"organization"</span> <span class="p">:</span> <span class="s">"my_org"</span><span class="p">,</span>
+ <span class="s">"applicationName"</span> <span class="p">:</span> <span class="s">"my_app"</span>
+<span class="p">}</span>
+</pre></div>
+</div>
+<p>To retrieve a particular review written by Jennie, you could use
+something like the following:</p>
+<div class="highlight-python"><div class="highlight"><pre>GET http://api.usergrid.com/my_org/my_app/users/jennie/wrote/reviews/<review_uuid>
+</pre></div>
+</div>
+<p>You can create connections to set up relationships you can use to later
+retrieve data quickly and with a simple syntax.</p>
+<p>For example, when creating a connected entity (such as the review entity
+here), you can at the same time create other connections to connect the
+product to the new review, then connect the product to its reviewer
+(paths are abbreviated in these examples):</p>
+<div class="highlight-python"><div class="highlight"><pre>POST /users/jennie/wrote/reviews {<review_entity_json>}
+POST /products/<reviewed_product_uuid>/reviewedIn/reviews/<new_review_uuid>
+POST /products/<reviewed_product_uuid>/reviewedBy/users/jennie
+</pre></div>
+</div>
+<p>Having created these connections for each review you post, in addition
+to getting the review the user wrote, you could later also:</p>
+<p>Get the reviews for a product:</p>
+<div class="highlight-python"><div class="highlight"><pre>GET /products/<reviewed_product_uuid>/reviewedIn/reviews
+Get the users who reviewed the product:
+GET /products/<reviewed_product_uuid>/reviewedBy/users
+</pre></div>
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