There are lots of confusion in people related to How to see the SQLite database? While developing the application either we provide the pre-populated database or make the database at runtime but in both cases, we can not see the database of the device directly.
If we talk about the database that we make in runtime then we can understand that but most people get confused in the second case when we use the pre-populated database. So let me clear that. Hope you got my point. So here are the steps to see the SQLite database of the app installed in a particular device:. If you are working with the Real Device, you can connect it with the development machine or if you are using emulator then you are ready for the next point. It will open the Android project.
If you have successfully found the option then you can click on it. After clicking on it, you will see a window. At the top of that window, you can see a dropdown with a list of devices connected with your development machine also includes emulators. Select the device from which you want to see the Realm database.
Select the device and expand the data option. Expand the application package directory and expand the database directory under that. You can see the database you have created.
After finding the database right click on that and save it to any directory. Please save the database on a known location. Here are some typical statements that create and delete a table:.
Just like files that you save on the device's internal storage , Android stores your database in your app's private folder. Your data is secure, because by default this area is not accessible to other apps or the user.
When you use this class to obtain references to your database, the system performs the potentially long-running operations of creating and updating the database only when needed and not during app startup. All you need to do is call getWritableDatabase or getReadableDatabase.
Note: Because they can be long-running, be sure that you call getWritableDatabase or getReadableDatabase in a background thread. See Threading on Android for more information. You may also want to implement the onDowngrade or onOpen methods, but they are not required. For example, here's an implementation of SQLiteOpenHelper that uses some of the commands shown above:. Insert data into the database by passing a ContentValues object to the insert method:.
The first argument for insert is simply the table name. The second argument tells the framework what to do in the event that the ContentValues is empty i. If you specify the name of a column, the framework inserts a row and sets the value of that column to null.
If you specify null , like in this code sample, the framework does not insert a row when there are no values. The insert methods returns the ID for the newly created row, or it will return -1 if there was an error inserting the data.
This can happen if you have a conflict with pre-existing data in the database. To read from a database, use the query method, passing it your selection criteria and desired columns.
The method combines elements of insert and update , except the column list defines the data you want to fetch the "projection" , rather than the data to insert. The results of the query are returned to you in a Cursor object. Because the arguments are provided separately from the selection query, they are escaped before being combined.
This makes your selection statements immune to SQL injection. For more detail about all arguments, see the query reference. To look at a row in the cursor, use one of the Cursor move methods, which you must always call before you begin reading values.
Since the cursor starts at position -1, calling moveToNext places the "read position" on the first entry in the results and returns whether or not the cursor is already past the last entry in the result set.
For each row, you can read a column's value by calling one of the Cursor get methods, such as getString or getLong. For each of the get methods, you must pass the index position of the column you desire, which you can get by calling getColumnIndex or getColumnIndexOrThrow.
When finished iterating through results, call close on the cursor to release its resources. For example, the following shows how to get all the item IDs stored in a cursor and add them to a list:. To delete rows from a table, you need to provide selection criteria that identify the rows to the delete method.
The mechanism works the same as the selection arguments to the query method. It divides the selection specification into a selection clause and selection arguments. The clause defines the columns to look at, and also allows you to combine column tests. The arguments are values to test against that are bound into the clause. The return value for the delete method indicates the number of rows that were deleted from the database.
When you need to modify a subset of your database values, use the update method. The return value of the update method is the number of rows affected in the database. Since getWritableDatabase and getReadableDatabase are expensive to call when the database is closed, you should leave your database connection open for as long as you possibly need to access it. Typically, it is optimal to close the database in the onDestroy of the calling Activity.
For more information, see how to how to issue shell commands. Content and code samples on this page are subject to the licenses described in the Content License. App Basics. Build your first app. App resources. Resource types. App manifest file. Device compatibility. Multiple APK support. Tablets, large screens, and foldables. Build responsive UIs. Build for foldables. Getting started. Handling data. User input. Watch Face Studio. Health services. Creating watch faces. Android TV. Build TV Apps.
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Wait until your emulator starts working. You can also open the DDMS from:. Click on "databases". On the left-hand side, you will see the name of the table created by you under "tables". Next Recommended Reading. Windows 10 Vs Windows Visual Studio Vs Visual Studio Understanding Matplotlib With Examples. Understanding Numpy With Examples.
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