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Android SQLiteDatabase Query SQL Logic Error or Missing Database

开发者 https://www.devze.com 2023-03-09 20:38 出处:网络
So I created a database using SQLiteOpenHelper and I\'m trying to query it. It returns the cursor but when I call moveToFirst() it crashes with the error SQL Logic Error or Missing Database.

So I created a database using SQLiteOpenHelper and I'm trying to query it. It returns the cursor but when I call moveToFirst() it crashes with the error SQL Logic Error or Missing Database.

I follow this websites code to create and query my database: http://www.vogella.de/articles/AndroidSQLite/article.html

EDIT:

My Database:

public class Database{
     private static final String DATABASE_NAME = "MyDatabase";
     private static final int DATABASE_VERSION = 1;
     private static final String TABLE_NAME = "MyTable";

     // Column Names
     public static final String ID = "_id";                 // INTEGER
     public static final String NUMBER = "number";          // TEXT

     private SQLiteDatabase database;
     private DatabaseHelper mDatabaseOpenHelper;

     public Database(Context context){
          mDatabaseOpenHelper = new DatabaseHelper(context);
          database = mDatabaseOpenHelper.getWritableDatabase();
     }

     public void close(){
          database.close();
     }

     public long addNumber(String number){
          ContentValues values = new ContentValues();
          values.put(NUMBER, number);
          return database.insert(TABLE_NAME, null, values);
     }

     public Cursor getNumber(String number){
          String selection = NUMBER + " MATCH ?";
          String[] selectionArgs = new String[] {number};
          return database.query(TABLE_NAME, null, selection, 开发者_开发知识库selectionArgs, null, null, null);
     }

     private class DatabaseHelper extends SQLiteOpenHelper{

          private static final String CREATE_TABLE = "CREATE TABLE " + TABLE_NAME + "(_id INTEGER PRIMARY KEY AUTOINCREMENT, " + NUMBER + " TEXT)";

          public DatabaseHelper(Context context){
               super(context, DATABASE_NAME, null, DATABASE_VERSION);
          }

          public void onCreate(SQLiteDatabase db) {
               db.execSQL(CREATE_TABLE);
          }

          public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
               db.execSQL("DROP TABLE IF EXISTS " + TABLE_NAME);
               onCreate(db);
          }
      }
 }

And this is how I query:

 Database database = new Database(this);

 Cursor cursor = database.getTrUpdate("1234");

 if (cursor.moveToFirst()){
      do{
           int d = cursor.getInt(cursor.getColumnIndex(Database.ID));
      } while(cursor.moveToNext());
 }


I think the error has something to do with selection and selectionArgs in my getNumber method, cause if I remove them there is no problem.


Have you checked if the array it returns is not empty?

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