在Sqflite中插入多个记录

时间：2019-05-30 07:51:17

标签： sqlite flutter sqflite

如何在sqflite中快速插入多个记录？标准的快速方法是：

await database.insert(table, object.toMap())

但是我不认为插入记录与循环一对一是一个好主意。 或者我可以在交易中插入所有列表？

7 个答案:

答案 0 :(得分：1)

在这种情况下，您可以使用批处理。 

batch = db.batch();
batch.insert('Test', {'name': 'item'});
batch.update('Test', {'name': 'new_item'}, where: 'name = ?', whereArgs: ['item']);
batch.delete('Test', where: 'name = ?', whereArgs: ['item']);
results = await batch.commit();

大批量，您可以使用await batch.commit(noResult: true);

答案 1 :(得分：1)

正如我在评论中提到的，您可以使用Batch。这是示例。 

Batch batch = db.batch();
batch.insert('Test', {'name': 'item'});
batch.update('Test', {'name': 'new_item'}, where: 'name = ?', whereArgs: ['item']);
batch.delete('Test', where: 'name = ?', whereArgs: ['item']);

现在，如果您要查找结果（这会花费一些内存），请使用

results = await batch.commit();

如果您正在寻找快速的性能，只需忽略结果并使用

await batch.commit(noResult: true);

Source

答案 2 :(得分：1)

如果您有要插入的对象列表，则可以这样进行操作（这不是很干净的代码，但是可以使用）：

  insertClients(List<Client> clients) async {
    final db = await database;
    var buffer = new StringBuffer();
    clients.forEach((c) {
      if (buffer.isNotEmpty) {
        buffer.write(",\n");
      }
      buffer.write("('");
      buffer.write(c.firstName);
      buffer.write("', '");
      buffer.write(c.lastName);
      buffer.write("', '");
      buffer.write(c.address);
      buffer.write("')");
    });
    var raw =
        await db.rawInsert("INSERT Into Clients (firstName,lastName,address)"
            " VALUES ${buffer.toString()}");
    return raw;
  }

我正在使用SQLite中的以下语句：

INSERT INTO 'tablename' ('column1', 'column2') VALUES
                ('data1', 'data2'),
                ('data1', 'data2'),
                ('data1', 'data2');

答案 3 :(得分：0)

我看到了使用数据库事务的可能性，这与Android非常相似。 我发现最好使用它们，在这里我展示了一个示例代码，如果它对某人有用的话。 在我的示例中显示了try-catches，但是可以使用Future函数回调来获得更简洁的代码：

Future<List<dynamic>> insertAll(String table, List<dynamic> objects) async {
List<dynamic> listRes = new List();
var res;
try {
  await DbHelper().database.transaction((db) async {
    objects.forEach((obj) async {
      try {
        var iRes = await db.insert(table, obj.toMap());
        listRes.add(iRes);
      } catch (ex) {
        DbHelper().databaseLog(CON_INSERT_MULTIPLE, "Error!", ex);
      }
    });
  });
  DbHelper().databaseLog(CON_INSERT_MULTIPLE, table, listRes);
  res = listRes;
} catch (er) {
  res = OutComeCallClient.ERROR;
  DbHelper().databaseLog(CON_INSERT_MULTIPLE, "Error!", er);
}
return res;

}

答案 4 :(得分：0)

这是我的代码，也许可以帮忙;） 感谢MihaiV。

insertOrUpdateAll(List<Map<String, dynamic>> ticks) async {

    if (ticks.length == 0) return null;
    final columns = ticks.first.keys.join(",");

    var valuesBuffer = new StringBuffer();
    ticks.forEach((task) {
      if (valuesBuffer.isNotEmpty) valuesBuffer.write(",\n");
      valuesBuffer.write("(");

      int ix = 0;
      task.forEach((key, value) {
        if (ix++ != 0) valuesBuffer.write(',');

        final isString =
            columnsInfo.where((c) => c.name == key).first.type == RowType.text;
        if (isString) valuesBuffer.write("'$value'");

        valuesBuffer.write(value);
      });

      valuesBuffer.write(")");
    });

    return await db.rawInsert("INSERT Into Clients ($columns)"
        " VALUES ${valuesBuffer.toString()}");
}

答案 5 :(得分：0)

   Model



 import 'package:sqflite/sqflite.dart';
    import 'package:path/path.dart';
    
    final String tableName = "todom";
    final String Column_id = "id";
    final String Column_name = "name";
    
    class TaskModel{
      final String name;
      int id;
    
      TaskModel({this.name, this.id});
    
      Map<String, dynamic> toMap(){
        return {
          Column_name : this.name
        };
      }
    }
    
    class TodoHelper{
      Database db;
    
      TodoHelper(){
        initDatabase();
      }
    
      Future<void> initDatabase() async{
        db = await openDatabase(
          join(await getDatabasesPath(), "databse.db"),
          onCreate: (db, version){
            return db.execute("CREATE TABLE $tableName($Column_id INTEGER PRIMARY KEY AUTOINCREMENT, $Column_name TEXT)");
          },
          version: 1
        );
      }
    
      Future<void> insertTask(TaskModel task) async{
        try{
          db.insert(tableName, task.toMap(), conflictAlgorithm: ConflictAlgorithm.replace);
        }catch(_){
          print(_);
        }
      }
    
      Future<List<TaskModel>> getAllTask () async{
        final List<Map<String, dynamic>> tasks = await db.query(tableName);
    
        return List.generate(tasks.length, (i){
          return TaskModel(name: tasks[i][Column_name], id: tasks[i][Column_id]);
        });
      }
    
    
    }




main.dart



import 'package:flutter/material.dart';

import 'TaskModel.dart';

void main() => runApp(MyApp());

class MyApp extends StatelessWidget {
  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        // This is the theme of your application.
        //
        // Try running your application with "flutter run". You'll see the
        // application has a blue toolbar. Then, without quitting the app, try
        // changing the primarySwatch below to Colors.green and then invoke
        // "hot reload" (press "r" in the console where you ran "flutter run",
        // or simply save your changes to "hot reload" in a Flutter IDE).
        // Notice that the counter didn't reset back to zero; the application
        // is not restarted.
        primarySwatch: Colors.blue,
      ),
      home: MyHomePage(),
    );
  }
}

class MyHomePage extends StatefulWidget {
  @override
  _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  final textController = TextEditingController();

  List<TaskModel> tasks = [];

  TaskModel currentTask;



  @override
  Widget build(BuildContext context) {
    final TodoHelper _todoHelper = TodoHelper();
    return Scaffold(
      body: Container(
        padding:EdgeInsets.all(32),
        child: Column(
          children: <Widget>[
            TextField(
              controller: textController,
            ),
            FlatButton(
              child: Text("Insert"),
              onPressed: (){
                currentTask = TaskModel(name: textController.text);
                _todoHelper.insertTask(currentTask);
              },
              color: Colors.blue,
              textColor: Colors.white,
            ),
            FlatButton(
              child: Text("Show All Task"),
              onPressed: () async{
                List<TaskModel> list = await _todoHelper.getAllTask();

                setState(() {
                  tasks = list;
                });
              },
              color: Colors.red,
              textColor: Colors.white,
            ),

            Expanded(
              child: ListView.separated(
                  itemBuilder: (context, index){
                    return ListTile(
                      leading: Text("${tasks[index].id}"),
                      title: Text("${tasks[index].name}"),
                    );
                  },
                  separatorBuilder: (context, index) => Divider(),
                  itemCount: tasks.length,

              ),
            )
          ],
        ),
      ),
    );
  }
}

答案 6 :(得分：0)

您可以尝试使用 rawInsert

Database db = await instance.database;
String sql = '''
INSERT INTO p_tasklistproviderobjective (
    idticket,
    objective
  ) VALUES (?, ?)
''';
//you can get this data from json object /API
List<Map> data = [
  {"idticket": 5, "objective": "dono"},
  {"idticket": 6, "objective": "dono2"},
  {"idticket": 7, "objective": "dono3"},
  {"idticket": 8, "objective": "dono4"},
];
//and then loop your data here
data.forEach((element) async {
  await db.rawInsert(sql, [element['idticket'], element['objective']]);
});
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