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Creating tables in sqlite database on android

由 主宰稳场 提交于 2019-11-29 07:15:29
EvilDuck

First of all I would recommend using android.util.Log for logging exceptions in Android.

Second - I suspect you have tables with wrong names created. Your error says query can't find "log", but I see you make some concatenation in "CREATE" statement. That may be the reason.

You can check what is actually created for you. By viewing the sqlite base created.

You can try:

  1. adb shell
  2. cd /data/data/<your.package.name>/databases
  3. sqlite3 <yourdbname>
  4. .tables

this will help you i have tried it and its also working

this is just an example 

public class DatabaseMarks {

    public static final String KEY_STUID = "stuid";
    public static final String KEY_SUB1 = "subject_one";
    public static final String KEY_SUB2 = "subject_two";
    public static final String KEY_SUB3= "subject_three";
    public static final String KEY_MARKS1= "marks_one";
    public static final String KEY_MARKS2 = "marks_two";
    public static final String KEY_MARKS3 = "marks_three";

    private static final String DATABASE_NAME = "Student";
    private static final String DATABASE_MARKSTABLE = "StudentMarks";
    private static final int DATABASE_VERSION = 1;

    private DbHelper ourHelper;
    private final Context ourContext;
    private SQLiteDatabase ourDatabase;

    private static class DbHelper extends SQLiteOpenHelper{

        public DbHelper(Context context) {
            super(context, DATABASE_NAME, null, DATABASE_VERSION);
            // TODO Auto-generated constructor stub
        }

        @Override
        public void onCreate(SQLiteDatabase db) {
            // TODO Auto-generated method stub
                db.execSQL(" CREATE TABLE " + DATABASE_MARKSTABLE + " (" +
                    KEY_STUID + " TEXT PRIMARY KEY, " +
                    KEY_SUB1 + " TEXT NOT NULL, " +
                    KEY_SUB2 + " TEXT NOT NULL, " +
                    KEY_SUB3 + " TEXT NOT NULL, " +
                    KEY_MARKS1 + " INTEGER NOT NULL, " +
                    KEY_MARKS2 + " INTEGER NOT NULL, " +
                    KEY_MARKS3 + " INTEGER NOT NULL);"
            );
        }

        @Override
        public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
            // TODO Auto-generated method stub

            db.execSQL("DROP TABLE IF EXISTS " + DATABASE_MARKSTABLE);
            onCreate(db);
        }

    }
    public DatabaseMarks(Context c){
        ourContext = c;
    }
    public DatabaseMarks open()throws SQLException{
        ourHelper = new DbHelper(ourContext);
        ourDatabase = ourHelper.getWritableDatabase();
        return this;
    }
    public void close(){
        ourHelper.close();
    }
    public long createInsert(String stuid, String subject1, String subject2,
            String subject3, String marks1, String marks2, String marks3) {
        // TODO Auto-generated method stub
        ContentValues cv = new ContentValues();
        cv.put(KEY_STUID, stuid);
        cv.put(KEY_SUB1, subject1);
        cv.put(KEY_SUB2, subject2);
        cv.put(KEY_SUB3, subject3);
        cv.put(KEY_MARKS1, marks1);
        cv.put(KEY_MARKS2, marks2);
        cv.put(KEY_MARKS3, marks3);
        return ourDatabase.insert(DATABASE_MARKSTABLE, null, cv);

    }

Remove DATABASE_NAME part of your SQLs.

If you want NOPO your database name, and want to create a table log, then:

private static class DatabaseHelper extends SQLiteOpenHelper {

    DatabaseHelper(Context context) {
        super(context, "NOPO", null, 2);
    }

    @Override
    public void onCreate(SQLiteDatabase db) {
        db.execSQL("CREATE TABLE " + "log" + " ("
                + KEY_TIME +" INTEGER primary key, "
                + KEY_TEXT +" TEXT not null);");
    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
        Log.w(TAG, "Upgrading database from version " + oldVersion + " to "
                + newVersion + ", which will destroy all old data");
        db.execSQL("DROP TABLE IF EXISTS log");
        onCreate(db);
    }
}

super(context, "NOPO", null, 2); makes this DatabaseHelper object just in the NOPO database environment, so you need not to specify it in SQL.

ps. I hardcode something and you should AVOID it.

public class LoginDataBaseAdapter { static final String DATABASE_NAME = "login.db";

    static final int DATABASE_VERSION = 1;

    public static final int NAME_COLUMN = 1;

    // TODO: Create public field for each column in your table.
    // SQL Statement to create a new database.

    static final String DATABASE_CREATE = "create table "+"LOGIN"+
                                 "( " +"ID"+" integer primary key autoincrement,"+ "USERNAME  text,PASSWORD text,UNAME text); ";

    // Variable to hold the database instance
    public  SQLiteDatabase db;

    // Context of the application using the database.
    private final Context context;

    // Database open/upgrade helper
    private DataBaseHelper dbHelper;

    public  LoginDataBaseAdapter(Context _context) 
    {
        context = _context;
        dbHelper = new DataBaseHelper(context, DATABASE_NAME, null, DATABASE_VERSION);

    }
    public  LoginDataBaseAdapter open() throws SQLException 
    {
        db = dbHelper.getWritableDatabase();
        return this;
    }
    public void close() 
    {
        db.close();
    }

    public  SQLiteDatabase getDatabaseInstance()
    {
        return db;
    }

            public class DBHandler extends SQLiteOpenHelper {
                private static String DATABASE_NAME = "mydb";
                private static int DATABASE_VERSION = 1;

                String TABLE_NAME = "Student";

                String KEY_ID = "id";
                String KEY_STUDENT_NAME = "name";
                String KEY_STUDENT_MARKS = "marks";

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

        @Override
            public void onCreate(SQLiteDatabase db) {
                // creating table
                String query = "CREATE TABLE " + TABLE_NAME +
                        " ( " +
                        KEY_ID + " INTEGER PRIMARY KEY," +
                        KEY_STUDENT_NAME + " TEXT," +
                        KEY_STUDENT_MARKS + " INTEGER"
                        " ) ";
                db.execSQL(query);

            // insertion in the table
            ContentValues values = new ContentValues();
            values.put(KEY_QUESTION_ID, "1");
            values.put(KEY_STUDENT_NAME , "abc");
            values.put(KEY_STUDENT_MARKS , "95");
            db.insert(TABLE_NAME, null, values);

            values.put(KEY_QUESTION_ID, "2");
            values.put(KEY_STUDENT_NAME , "def");
            values.put(KEY_STUDENT_MARKS , "93");
            db.insert(TABLE_NAME, null, values);
    }
        @Override
        public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
            // TODO Auto-generated method stub

            db.execSQL("DROP TABLE IF EXISTS " + TABLE_NAME);
            // Create tables again
            onCreate(db);
        }
     // retrieve date
     List<Student> getAllData(int Id) {

            List<Student> student = new ArrayList<Student>();
            // Select All Query
            String selectQuery = "SELECT * FROM " + TABLE_NAME + "    WHERE KEY_ID =" + "'" + Id + "'";

            SQLiteDatabase db = this.getWritableDatabase();

            Cursor cursor = db.rawQuery(selectQuery, null);

            // looping through all rows and adding to list
            if (cursor.moveToFirst()) {
                do {
                    Student std = new Student();
                    u.setId(cursor.getInt(0));
                    u.setStudentName(cursor.getString(1));
                    u.setMarks(cursor.getString(2));

                    student.add(std);
                } while (cursor.moveToNext());
            }
            // return student list
            return student;
        }
    }

     public class Student {

        public static int Id;
        public static String studentName;
        public static int marks;

        public int getId() {
            return Id;
        }

        public static void setId(int id) {
            Id = id;
        }

        public String getStudentName() {
            return studentName;
        }

        public static void setStudentName(String studentName) {
            Student.studentName = studentName;
        }

        public int getMarks() {
            return marks;
        }

        public static void setMarks(int marks) {
            Student.marks = marks;
        }
    }

    public class MainActivity extends AppCompatActivity {

        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_main);

            DBHandler db = new DBHandler(getApplicationContext());
            List<Student> std = new ArrayList<Student>();
            rl = db.getAllData(1);
           for (Student s : std) {
               Log.v("Id",s.getId());
               Log.v("Name",s.getStudentName());
               Log.v("Marks",s.getMarks());
       }
    }
}
标签
android
sqlite
android-logcat
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