Question

我有应用程序与数据库
我想在进入数据库之前检查数据库中的数据如果数据与数据库相等则无法进入，如果数据不相等则可以进入
这是我的一些代码：

public void saveData(){
    long tim = System.currentTimeMillis();
    SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd kk:mm:ss");
    String curTime = df.format(tim);
    Cursor c = helper.getNoOrder();
    c.moveToFirst();
    if(c.getCount() != 0){
        System.out.println("klik");
        if(noOrder.getText().toString().equals(c.getString(0))){
            Toast.makeText(this, "No Order Sudah Terdaftar", Toast.LENGTH_LONG).show();
        }else{
            helper.insertBeli123(noOrder.getText().toString(), item.getText().toString(), 
                    custName.getText().toString(), custTelp.getText().toString(),
                    qty.getText().toString(),temp.getText().toString(),temp.getText().toString(),
                    temp.getText().toString(), curTime);
            Toast.makeText(this, "Data berhasil disimpan", Toast.LENGTH_LONG).show();
            finish();
        }
    }else{
        helper.insertBeli123(noOrder.getText().toString(), item.getText().toString(), 
                custName.getText().toString(), custTelp.getText().toString(),
                qty.getText().toString(),temp.getText().toString(),temp.getText().toString(),
                temp.getText().toString(), curTime);
        Toast.makeText(this, "Data berhasil disimpan", Toast.LENGTH_LONG).show();
        finish();
    }
    //startActivity(new Intent(this,Direktori.class));
}

在我的DBhelper中这样：

public void onCreate(SQLiteDatabase db) {
    db.execSQL("CREATE TABLE tanda_terima (_id integer primary key AUTOINCREMENT,no_order text " +
            ",item text,cust_id text,cust_name text,cust_telp text,quantity text,order_nik text" +
            ",pengirim text,penerima text,gambar text,waktu_ambil datetime,flag integer)");
    db.execSQL("CREATE TABLE image (_id integer primary key AUTOINCREMENT,no_order text ,image text,tgl_buat datetime,flag integer)");
    db.execSQL("CREATE TABLE user (user text primary key,no_imei integer,password text)");
    db.execSQL("CREATE TABLE log_sync_tanda (no_order text primary key,status text ,waktu_sync datetime)");
    db.execSQL("CREATE TABLE log_sync_image (image text primary key,kdstore text,status text ,waktu_sync datetime)");
}
 public void insertBeli123(String no_order,String item,String cust_name
        ,String cust_telp,String quantity,String pengirim,String penerima,
        String gambar,String waktu){

    ContentValues cv = new ContentValues();
    cv.put("no_order", no_order);
    cv.put("item", item);
    cv.put("cust_name", cust_name);
    cv.put("cust_telp", cust_telp);
    cv.put("quantity", quantity);
    cv.put("pengirim", pengirim);
    cv.put("penerima", penerima);
    cv.put("gambar", gambar);
    cv.put("waktu_ambil", waktu);

    getWritableDatabase().insert("tanda_terima", "name", cv);
}
    public Cursor getNoOrder(){
    return(getReadableDatabase().rawQuery("SELECT no_order FROM tanda_terima", null));
}

Answer 1

检查源代码。它可以帮助您检查重复的数据。

String sql = "select * from "
                + TABLE_NAME + " WHERE placeId = '" + placeId + "'"; 
        Cursor cursorinfo = null; 
        try {
            database = databaseHelper.getReadableDatabase();
            cursorinfo = database.rawQuery(sql, null);
        } catch (Exception ex) {
            ex.printStackTrace();
        }

        if (!cursorinfo.moveToFirst()) {
                        database = databaseHelper.getWritableDatabase();
            try {
                database.insert(TABLE_NAME, "", values/// Here ContentValues);
            } finally {
                database.close();
                cursorinfo.close();
            }
        }

我认为它对你有帮助。感谢

Answer 2

首先，您需要从游标

中的数据库中获取整个数据

 void insertInDatabase()
 {
    Cursor cursor=fetchDataFromDatabase();
    if(!cursor.getCount==0)
    {
         while(cursor.moveToNext())
          {
               if(!(cursor.getString(1).equals("Harneet"))
               {
                     dbAdapter.insert("Harneet");
                     return;
               }
          }
          System.println("Record ALready exists in Database");
    }
    else
    {
              System.println("Empty Database");
              dbAdapter.insert("Harneet");
    }
  }

    /*Assume that we have two fields in database, one is Primary key and other is Name field*/

在DbHelper中写下这个：

在数据库中插入值

     void insert(String name)
     { 
           ContentValues cv=new ContentValues();
           cv.put("NAME",name);
           getWritableDatabase.insert(TABLE_NAME,null,cv);
     }

获取光标值

     public Cursor fetchDataFromDatabase()
     {
          String col[]={_id,name};
         getReadableDatabase.query(TABLE_NAME,col,null,null,null);
     }

检查数据库android中的重复数据

2 个答案: