Android Studio SQLite Error: "no such column.."

Android Studio SQLite Error: "no such column.."

当我的应用程序创建数据库时,它似乎没有创建列 'cardname'。我一直在查看我的代码,但找不到我做错了什么。任何人都可以帮我吗?

DBAdapter class

public class DBAdapter {
static final String KEY_ROWID = "_id";
static final String KEY_USERNAME = "name";
static final String KEY_PASSWORD = "password";
static final String KEY_CARDNUM = "cardnum";
static final String KEY_CARDNAME = "cardname";
static final String TAG = "DBAdapter";

static final String DATABASE_NAME = "CPDB";
static final String DATABASE_TABLE = "Users";
static final int DATABASE_VERSION = 1;

static final String DATABASE_CREATE =
        "create table Users (_id integer primary key autoincrement, "
                + "name text not null,"
                  +"password text not null,"
                   +"cardnum text not null,"
                    + "cardname text not null"
                      + ");";


final Context context;

DatabaseHelper DBHelper;
SQLiteDatabase db;

public DBAdapter (Context ctx){
    this.context = ctx;
    DBHelper = new DatabaseHelper(context);
}

private static class DatabaseHelper extends SQLiteOpenHelper
{
    DatabaseHelper(Context context){
        super (context, DATABASE_NAME, null, DATABASE_VERSION);
    }

    @Override
    public void onCreate(SQLiteDatabase db){
        try{
            db.execSQL(DATABASE_CREATE);
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }

    @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 Users");
        onCreate (db);

    }
}

DBAdapter里面的查询class

  //--retrieves cards for the user--
public Cursor getCards(String username) throws SQLException{
    Cursor mCursor =
            db.query(true, DATABASE_TABLE, new String[] {KEY_ROWID, KEY_USERNAME, KEY_CARDNAME}, KEY_USERNAME + "= '" + username + "'", null, null, null, null,null);
    if (mCursor != null) {
        mCursor.moveToFirst();
    }
    return mCursor;
}

Main Activity Class (出现错误时)..

  if (view.getId() == R.id.bttn_show)
    {
        EditText username = (EditText) findViewById(R.id.tf_username);
        String tesco = "tesco";

        DBAdapter db= new DBAdapter(this);

    db.open();
    Cursor c = db.getCards(username.getText().toString());

    ArrayList<String> usersCards = new ArrayList<>();

    if(c.moveToFirst()) {
        do {
            String aCard = c.getString(c.getColumnIndex("cardname"));
            usersCards.add(aCard);

        } while (c.moveToNext());

    }
    if (usersCards.contains(tesco)) {
        ImageButton tb1 = (ImageButton) findViewById(R.id.ib_1);

        tb1.setBackgroundResource(R.drawable.tesco);

    }
    else {
        Toast.makeText(this, "Please Add a Card", Toast.LENGTH_LONG).show();
    }
}

Logcat 错误日志

        --------- beginning of crash
02-07 13:13:08.100    2109-2109/com.cardpocket.cardpocket E/AndroidRuntime﹕ FATAL EXCEPTION: main
Process: com.cardpocket.cardpocket, PID: 2109
java.lang.IllegalStateException: Could not execute method of the activity
        at android.view.View.onClick(View.java:4007)
        at android.view.View.performClick(View.java:4756)
        at android.view.View$PerformClick.run(View.java:19749)
        at android.os.Handler.handleCallback(Handler.java:739)
        at android.os.Handler.dispatchMessage(Handler.java:95)
        at android.os.Looper.loop(Looper.java:135)
        at android.app.ActivityThread.main(ActivityThread.java:5221)
        at java.lang.reflect.Method.invoke(Native Method)
        at java.lang.reflect.Method.invoke(Method.java:372)
        at         com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)
     Caused by: java.lang.reflect.InvocationTargetException
        at java.lang.reflect.Method.invoke(Native Method)
        at java.lang.reflect.Method.invoke(Method.java:372)
        at android.view.View.onClick(View.java:4002)
 



 at android.view.View.performClick(View.java:4756)
            at android.view.View$PerformClick.run(View.java:19749)
            at android.os.Handler.handleCallback(Handler.java:739)
            at android.os.Handler.dispatchMessage(Handler.java:95)
            at android.os.Looper.loop(Looper.java:135)
            at android.app.ActivityThread.main(ActivityThread.java:5221)
            at java.lang.reflect.Method.invoke(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:372)
            at     com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)
 Caused by: android.database.sqlite.SQLiteException: no such column:     cardname (code 1): , while compiling: SELECT DISTINCT _id, name, cardname FROM Users WHERE name= 'cliff'
        at     android.database.sqlite.SQLiteConnection.nativePrepareStatement(Native Method)
        at     android.database.sqlite.SQLiteConnection.acquirePreparedStatement(SQLiteConnecti    on.java:889)
        at     android.database.sqlite.SQLiteConnection.prepare(SQLiteConnection.java:500)
        at     android.database.sqlite.SQLiteSession.prepare(SQLiteSession.java:588)
        at android.database.sqlite.SQLiteProgram.<init>    (SQLiteProgram.java:58)
        at android.database.sqlite.SQLiteQuery.<init>(SQLiteQuery.java:37)
        at     android.database.sqlite.SQLiteDirectCursorDriver.query(SQLiteDirectCursorDriver.    java:44)
        at     android.database.sqlite.SQLiteDatabase.rawQueryWithFactory(SQLiteDatabase.java:1316)
        at     android.database.sqlite.SQLiteDatabase.queryWithFactory(SQLiteDatabase.java:1163)
        at     android.database.sqlite.SQLiteDatabase.query(SQLiteDatabase.java:1034)
        at com.cardpocket.cardpocket.DBAdapter.getCards(DBAdapter.java:148)
        at     com.cardpocket.cardpocket.mainactivity.onClick(mainactivity.java:78)
            at java.lang.reflect.Method.invoke(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:372)
            at android.view.View.onClick(View.java:4002)
            at android.view.View.performClick(View.java:4756)
            at android.view.View$PerformClick.run(View.java:19749)
            at android.os.Handler.handleCallback(Handler.java:739)
            at android.os.Handler.dispatchMessage(Handler.java:95)
            at android.os.Looper.loop(Looper.java:135)
            at android.app.ActivityThread.main(ActivityThread.java:5221)
            at java.lang.reflect.Method.invoke(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:372)
            at     com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)

提前致谢。

您似乎正在尝试获取不是在您的 DBAdapter class 中创建的 cardesc 列。你能 post 更多 logcat 日志吗?

table中是否有名为"tesco"的记录。

将 tesco 插入 table 后尝试搜索 tesco。