Let’s take a look at the classes and methods that allow us to use SQLitedatabases for more complex data-driven apps. Finally, we’ll query the data set we’ve recorded based on a certain device orientation we are looking for, and we’ll highlight the sensor value that matches our query criteria. We’ll use the recorded sensor values to create a time series visualization of the data. Then we’ll create an app that uses SQLite to capture accelerometer data from the sensor built into the Android. In this chapter, we’ll first get SQLite running with a simple sketch and learn how to use SQL queries to retrieve data from a SQLite table. This simple database management system can be used instead of disk files, like the tab- or comma-delimited text files we’ve worked with in Chapter 9, Working with Data, replacing them with ad-hoc SQLite disk files. It is often used in cellphones, tablet computers, set-top boxes, and appliances because SQLite does not require administration or maintenance. It works very well as a file format for applications like Computer-Aided Design ( CAD), financial software, and record keeping. It offers less fine-grained control over access to data than other systems like PostgreSQL or MySQL does, but it is simpler to use and administer, which is the main objective of the technology. SQLite is a fairly simple and fast system, is considered very reliable, and has a small footprint that can be embedded in larger programs. It implements the popular Structured Query Language ( SQL) syntax for database queries, which we can use to access data stored locally on our Android device. It’s not the best solution so any comments please discus below.In this second part of our introduction to data, we’ll work with SQLite, the popular relational database management system for local clients such as the Android, used also by many browsers and operating systems to store data. Public class MyDb extends SQLiteAssetHelper,Īlright, so that is that. Now we need to create a java class that uses the SQLiteAssetHelper: You need to place the database in: Project/app/src/main/assets.databases/mydb.db Shipping your App with an existing SQLite databaseįirst we need to add the dependency in adleĬompile ':sqliteassethelper:+' Where should I put the Existing SQLite file in the Android Project Structure I am unaware of the ability to do this with the native Android SDK. We do this using the following package: Android SQLite Asset Helper. So the database has to be copied over from the app to that location. The database is stored in /data/data/za.co.mydomain.myapp/databases/mydb.db. So basically use of an ORM is not applicable in this case as we want to ship the app with existing data. Note: If the above is not true please comment It will create tables exactly based on your models.It will create the database for you based on your models and hence can’t use existing data.Now if you have chosen to use an ORM take note of the following. activeandroid – A popular Android ORM ( Tutorial).androrm – Newer but promising take on a simple ORM.
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