{"id":6874,"date":"2019-05-09T14:32:33","date_gmt":"2019-05-09T21:32:33","guid":{"rendered":"http:\/\/www.couchbase.com\/blog\/?p=6874"},"modified":"2025-06-13T20:52:30","modified_gmt":"2025-06-14T03:52:30","slug":"tutorial-query-database-xamarin","status":"publish","type":"post","link":"https:\/\/www.couchbase.com\/blog\/tutorial-query-database-xamarin\/","title":{"rendered":"Xamarin App Using the Query API & Couchbase Lite Database"},"content":{"rendered":"

Couchbase Lite 2.x<\/a> is a powerful NoSQL<\/a> embedded data store for iOS, Android and .Net Mobile Platforms<\/a>. In an earlier tutorial<\/a>, we explored the basics of Database and Document CRUD<\/a> operations using Couchbase Lite within your Xamarin apps.<\/p>\n

In addition to the standard CRUD operations, Couchbase Lite brings powerful Query API<\/a> with SQL-like semantics and Full-Text-Search\u00a0(FTS)<\/a> capabilities to the edge. The previous tutorial<\/a> discussed the use of a single instance of Couchbase Lite embedded within your apps. In this one we show, you can, in fact, have multiple local instances of Couchbase Lite!<\/p>\n

We will explore a few additional capabilities of Couchbase Lite in a new tutorial<\/a> that we introduce here.<\/p>\n

Couchbase Lite + Xamarin Tutorial<\/h2>\n

The tutorial<\/strong><\/a> will walk you through a Xamarin solution that will demonstrate how you can bundle, load and use a prebuilt<\/em> instance of Couchbase Lite<\/strong><\/p>\n

In the previous tutorial<\/a>, we had a single instance of Couchbase Lite embedded within the app. In this tutorial, we will have two instances of Couchbase Lite. One instance holds data that is pre-loaded with the app and is common to all users of the app on the device. The second instance holds user-specific data.<\/p>\n

There are several reasons why you may want to bundle your app with a prebuilt database. This would be suited for data that does not change or change that often. This allows you to avoid the bandwidth and latency involved in fetching\/syncing this data from a remote server. This also improves the overall user experience by reducing the start-up time.<\/p>\n

The tutorial also introduces you to the basics of the QueryBuilder<\/code> interface. We will use a simple pattern matching query.<\/p>\n

App Overview<\/h2>\n

We will be extending the \u201cUser Profile\u201d app that we introduced in the Fundamentals Tutorial<\/a><\/p>\n

This version of the app does the following –<\/p>\n