How to check existing database before creating new database on android 2.2?

前端 未结 4 758
没有蜡笔的小新
没有蜡笔的小新 2021-01-22 12:48

I need to check existing database before creating new database on android 2.2. How to check it?

相关标签:
4条回答
  • 2021-01-22 13:04

    You should need to check database already exists or not, if not than create database else not create database. Please you can use below query.

    CREATE TABLE if not exists TABLE_NAME (key data_type);

    Call this query inside onCreate method.

    0 讨论(0)
  • 2021-01-22 13:08

    To check if your database was created you can use the following code and it will not be recreated every time you open the application. dbName = is the name of you DB

    public static boolean doesDatabaseExist(Context context, String dbName) {
            File dbFile = context.getDatabasePath(dbName);
            return dbFile.exists();
        }
    
    0 讨论(0)
  • 2021-01-22 13:14

    use openOrCreateDatabase method

    Read here

    ----- EDIT ------

    public boolean checkDataBase(){
    
        SQLiteDatabase checkDB = null;
    
        try{
            String myPath = DB_PATH + DB_NAME;
            checkDB = SQLiteDatabase.openDatabase(myPath, null, SQLiteDatabase.OPEN_READONLY | SQLiteDatabase.NO_LOCALIZED_COLLATORS);
    
        }catch(SQLiteException e){
    
            //database does't exist yet.
        }
    
        if(checkDB != null){
            checkDB.close();
        }
    
        return checkDB != null ? true : false;
    }
    
    0 讨论(0)
  • 2021-01-22 13:15

    Doesn't it work with the DatabaseHelper ? If you haven't tried here is code I posted before...

    Android - Sqlite database method undefined fot type

    0 讨论(0)
提交回复
热议问题