$flutter pub add sqflite path

import'dart:async';​import'package:flutter/widgets.dart';import'package:path/path.dart';import'package:sqflite/sqflite.dart';

classDog{finalintid;finalStringname;finalintage;​constDog({requiredthis.id,requiredthis.name,requiredthis.age});}

finaldatabase=openDatabase(// Set the path to the database. Note: Using the `join` function from the// `path` package is best practice to ensure the path is correctly// constructed for each platform.join(awaitgetDatabasesPath(),'doggie_database.db'),// When the database is first created, create a table to store dogs.onCreate:(db,version){// Run the CREATE TABLE statement on the database.returndb.execute('CREATE TABLE dogs(id INTEGER PRIMARY KEY, name TEXT, age INTEGER)',);},// Set the version. This executes the onCreate function and provides a// path to perform database upgrades and downgrades.version:1,);

classDog{finalintid;finalStringname;finalintage;​Dog({requiredthis.id,requiredthis.name,requiredthis.age});​// Convert a Dog into a Map. The keys must correspond to the names of the// columns in the database.Map<String,Object?>toMap(){return{'id':id,'name':name,'age':age};}​// Implement toString to make it easier to see information about// each dog when using the print statement.@overrideStringtoString(){return'Dog{id:$id, name:$name, age:$age}';}}

// Define a function that inserts dogs into the databaseFuture<void>insertDog(Dogdog)async{// Get a reference to the database.finaldb=awaitdatabase;​// Insert the Dog into the correct table. You might also specify the// `conflictAlgorithm` to use in case the same dog is inserted twice.//// In this case, replace any previous data.awaitdb.insert('dogs',dog.toMap(),conflictAlgorithm:ConflictAlgorithm.replace,);}

// Create a Dog and add it to the dogs tablevarfido=Dog(id:0,name:'Fido',age:35);​awaitinsertDog(fido);

// A method that retrieves all the dogs from the dogs table.Future<List<Dog>>dogs()async{// Get a reference to the database.finaldb=awaitdatabase;​// Query the table for all the dogs.finalList<Map<String,Object?>>dogMaps=awaitdb.query('dogs');​// Convert the list of each dog's fields into a list of `Dog` objects.return[for(final{'id':idasint,'name':nameasString,'age':ageasint}indogMaps)Dog(id:id,name:name,age:age),];}

// Now, use the method above to retrieve all the dogs.print(awaitdogs());// Prints a list that include Fido.

Future<void>updateDog(Dogdog)async{// Get a reference to the database.finaldb=awaitdatabase;​// Update the given Dog.awaitdb.update('dogs',dog.toMap(),// Ensure that the Dog has a matching id.where:'id = ?',// Pass the Dog's id as a whereArg to prevent SQL injection.whereArgs:[dog.id],);}

// Update Fido's age and save it to the database.fido=Dog(id:fido.id,name:fido.name,age:fido.age+7);awaitupdateDog(fido);​// Print the updated results.print(awaitdogs());// Prints Fido with age 42.

Future<void>deleteDog(intid)async{// Get a reference to the database.finaldb=awaitdatabase;​// Remove the Dog from the database.awaitdb.delete('dogs',// Use a `where` clause to delete a specific dog.where:'id = ?',// Pass the Dog's id as a whereArg to prevent SQL injection.whereArgs:[id],);}

import'dart:async';​import'package:flutter/widgets.dart';import'package:path/path.dart';import'package:sqflite/sqflite.dart';​voidmain()async{// Avoid errors caused by flutter upgrade.// Importing 'package:flutter/widgets.dart' is required.WidgetsFlutterBinding.ensureInitialized();// Open the database and store the reference.finaldatabase=openDatabase(// Set the path to the database. Note: Using the `join` function from the// `path` package is best practice to ensure the path is correctly// constructed for each platform.join(awaitgetDatabasesPath(),'doggie_database.db'),// When the database is first created, create a table to store dogs.onCreate:(db,version){// Run the CREATE TABLE statement on the database.returndb.execute('CREATE TABLE dogs(id INTEGER PRIMARY KEY, name TEXT, age INTEGER)',);},// Set the version. This executes the onCreate function and provides a// path to perform database upgrades and downgrades.version:1,);​// Define a function that inserts dogs into the databaseFuture<void>insertDog(Dogdog)async{// Get a reference to the database.finaldb=awaitdatabase;​// Insert the Dog into the correct table. You might also specify the// `conflictAlgorithm` to use in case the same dog is inserted twice.//// In this case, replace any previous data.awaitdb.insert('dogs',dog.toMap(),conflictAlgorithm:ConflictAlgorithm.replace,);}​// A method that retrieves all the dogs from the dogs table.Future<List<Dog>>dogs()async{// Get a reference to the database.finaldb=awaitdatabase;​// Query the table for all the dogs.finalList<Map<String,Object?>>dogMaps=awaitdb.query('dogs');​// Convert the list of each dog's fields into a list of `Dog` objects.return[for(final{'id':idasint,'name':nameasString,'age':ageasint}indogMaps)Dog(id:id,name:name,age:age),];}​Future<void>updateDog(Dogdog)async{// Get a reference to the database.finaldb=awaitdatabase;​// Update the given Dog.awaitdb.update('dogs',dog.toMap(),// Ensure that the Dog has a matching id.where:'id = ?',// Pass the Dog's id as a whereArg to prevent SQL injection.whereArgs:[dog.id],);}​Future<void>deleteDog(intid)async{// Get a reference to the database.finaldb=awaitdatabase;​// Remove the Dog from the database.awaitdb.delete('dogs',// Use a `where` clause to delete a specific dog.where:'id = ?',// Pass the Dog's id as a whereArg to prevent SQL injection.whereArgs:[id],);}​// Create a Dog and add it to the dogs tablevarfido=Dog(id:0,name:'Fido',age:35);​awaitinsertDog(fido);​// Now, use the method above to retrieve all the dogs.print(awaitdogs());// Prints a list that include Fido.​// Update Fido's age and save it to the database.fido=Dog(id:fido.id,name:fido.name,age:fido.age+7);awaitupdateDog(fido);​// Print the updated results.print(awaitdogs());// Prints Fido with age 42.​// Delete Fido from the database.awaitdeleteDog(fido.id);​// Print the list of dogs (empty).print(awaitdogs());}​classDog{finalintid;finalStringname;finalintage;​Dog({requiredthis.id,requiredthis.name,requiredthis.age});​// Convert a Dog into a Map. The keys must correspond to the names of the// columns in the database.Map<String,Object?>toMap(){return{'id':id,'name':name,'age':age};}​// Implement toString to make it easier to see information about// each dog when using the print statement.@overrideStringtoString(){return'Dog{id:$id, name:$name, age:$age}';}}