31.4. Data Persistence with SQLite in Flutter: Data Insertion

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Data persistence is a crucial part of any application. In Flutter, one of the most effective ways to accomplish this is using SQLite. SQLite is a relational database management system that is built into an application. It allows developers to efficiently and securely store, retrieve, and manipulate data.

In this chapter, we will focus on inserting data using SQLite in Flutter. Let's start with installing and configuring the SQLite plugin, and then move on to creating the database and tables. Finally, let's discuss how to insert data into SQLite table.

Installation and Configuration of SQLite

To start using SQLite in Flutter, we first need to install the 'sqflite' plugin. Add the following line to your project's 'pubspec.yaml' file:

dependencies:
  sqflite: any

After adding the dependency, run the command 'flutter packages get' in the terminal to install the package. We are now ready to start using SQLite in our Flutter application.

Creating the Database and Tables

Before we can insert data, we need to create a database and a table. In SQLite, a database is simply a file on the file system, and a table is a structure within the database that contains rows of data.

To create a database, we use sqflite's 'openDatabase' function, which returns a 'Database' object. This function accepts a path to the database file and an 'onCreate' callback function, which is called if the database does not exist.

The 'onCreate' function is where we create our tables. To create a table, we use the 'execute' function of the 'Database' object, which accepts an SQL string. Here is an example of how to create a database and table:

var database = await openDatabase(path, version: 1,
    onCreate: (Database db, int version) async {
  await db.execute(
    'CREATE TABLE my_table (id INTEGER PRIMARY KEY, name TEXT)',
  );
});

Entering Data

Now that we have a database and a table, we can start entering data. To insert data into an SQLite table, we use the 'insert' function of the 'Database' object. This function accepts the table name and a map of data to be inserted.

Here is an example of how to insert data into a table:

int id = await database.insert(
  'my_table',
  {'name': 'Bob'},
);

In this example, we are inserting a row into the table 'my_table' with the name 'Bob'. The 'insert' function returns the ID of the inserted row.

It is important to note that the 'insert' function only accepts data that matches the structure of the table. If we try to insert data that doesn't match the structure of the table, SQLite will throw an error.

Conclusion

SQLite is a powerful and efficient way to persist data in Flutter applications. In this chapter, we discuss how to install and configure SQLite, create a database and tables, and insert data. In the next chapter, we'll discuss how to retrieve, update, and delete SQLite data.

We hope you found this guide useful and that it gave you a good understanding of how to use SQLite in Flutter. Remember, practice makes perfect, so keep experimenting and building!

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25931.5. Data Persistence with SQLite in Flutter: Data Query