Cursor error in Android tells me column does not exist

Question

My app is required to return a cursor containing a bunch of quotes, depending on the author chosen. Right now, I am hard coding the application so it will return only one author's quotes.

The error is occurring in my cursor adapter parameters, setting the "to" column, it tells me that this column, "quote", does not exist.

I have tried changing the to parameter to KEY_QUOTE, and even tried changing the name of the actual database column but still now joy.

What am I doing wrong?

Below are the blocks of code used in this operation.

1. Creating the database table, Quotes
2. Populating this table
3. Querying for the quotes
4. Opening the database connection, cursor creation(where I am getting the actual error, with the "from" parameter)

1.

private static final String CREATE_QUOTE_TABLE = 

            "create table " + QUOTES_TABLE +
            " (_id integer primary key autoincrement, " + 
            "auth_name text not null, " +
            "myQuote text not null, " +
            "category text not null);";

2.

public long populateQuotes(){

    ContentValues initialValues = new ContentValues();

    long[] rowIds = new long[authorName.length];

    // Add wilson quotes category: Anthropology
    for(int i = 0; i < 3; i++){
        initialValues.put(KEY_AUTHNAME, authorName[3]);
        initialValues.put(KEY_QUOTE, quoteRAW[i]);
        initialValues.put(KEY_CATEGORY, category[0]);
        rowIds[i] = qmDB.insertOrThrow(QUOTES_TABLE, null, initialValues);
    }
    // Add wilson quotes category: RAW
    for(int i = 3; i < 5; i++){
        initialValues.put(KEY_AUTHNAME, authorName[3]);
        initialValues.put(KEY_QUOTE, quoteRAW[i]);
        initialValues.put(KEY_CATEGORY, category[1]);
        rowIds[i] = qmDB.insertOrThrow(QUOTES_TABLE, null, initialValues);

    }
    // Add wilson quotes category: Philosophy
    for(int i = 5; i < 11; i++){
        initialValues.put(KEY_AUTHNAME, authorName[3]);
        initialValues.put(KEY_QUOTE, quoteRAW[i]);
        initialValues.put(KEY_CATEGORY, category[2]);
        rowIds[i] = qmDB.insertOrThrow(QUOTES_TABLE, null, initialValues);

    }
    // Add wilson quotes category: General Semantics
    for(int i = 11; i < 12; i++){
        initialValues.put(KEY_AUTHNAME, authorName[3]);
        initialValues.put(KEY_QUOTE, quoteRAW[i]);
        initialValues.put(KEY_CATEGORY, category[3]);
        rowIds[i] = qmDB.insertOrThrow(QUOTES_TABLE, null, initialValues);

    }
    // Add wilson quotes category: Humor
    for(int i = 11; i < 12; i++){
        initialValues.put(KEY_AUTHNAME, authorName[3]);
        initialValues.put(KEY_QUOTE, quoteRAW[i]);
        initialValues.put(KEY_CATEGORY, category[4]);
        rowIds[i] = qmDB.insertOrThrow(QUOTES_TABLE, null, initialValues);

    }

    return rowIds[0];
}

3.

public Cursor getQuotes(){

    /*
    return qmDB.query(QUOTES_TABLE, new String[]{
            KEY_QUOTE
            },
            KEY_AUTHNAME + "=" + "'Robert Anton Wilson'",
            null,
            null,
            null,
            null);*/



    //String who = authorName[position];
    return qmDB.rawQuery("SELECT _id as _id from Quotes WHERE auth_name = ?",
            new String[]{"'Robert Anton Wilson'"});

}

4.

// Create DB connection and open.
    dbm = new MyDBManager(this);
    dbm.open();

    // Call for the quotes to be queried, store results in cursor.
    myCursor = dbm.getQuotes();
    myCursor.moveToFirst();

    // Column quote does not exist?
    SimpleCursorAdapter mAdapter = new SimpleCursorAdapter(this, R.layout.quoterow,                myCursor, new String[]{"myQuote"}, new int[]{R.id.quote});
    this.setListAdapter(mAdapter);

    myCursor.close();

For further clarification I have included the error log:

05-01 18:38:13.876: ERROR/AndroidRuntime(1455): FATAL EXCEPTION: main
05-01 18:38:13.876: ERROR/AndroidRuntime(1455): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.QuoteMachine/com.QuoteMachine.Quote}: java.lang.IllegalArgumentException: column 'myQuote' does not exist
05-01 18:38:13.876: ERROR/AndroidRuntime(1455):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2787)
05-01 18:38:13.876: ERROR/AndroidRuntime(1455):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2803)
05-01 18:38:13.876: ERROR/AndroidRuntime(1455):     at android.app.ActivityThread.access$2300(ActivityThread.java:135)
05-01 18:38:13.876: ERROR/AndroidRuntime(1455):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2136)
05-01 18:38:13.876: ERROR/AndroidRuntime(1455):     at android.os.Handler.dispatchMessage(Handler.java:99)
05-01 18:38:13.876: ERROR/AndroidRuntime(1455):     at android.os.Looper.loop(Looper.java:144)
05-01 18:38:13.876: ERROR/AndroidRuntime(1455):     at android.app.ActivityThread.main(ActivityThread.java:4937)
05-01 18:38:13.876: ERROR/AndroidRuntime(1455):     at java.lang.reflect.Method.invokeNative(Native Method)
05-01 18:38:13.876: ERROR/AndroidRuntime(1455):     at java.lang.reflect.Method.invoke(Method.java:521)
05-01 18:38:13.876: ERROR/AndroidRuntime(1455):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
05-01 18:38:13.876: ERROR/AndroidRuntime(1455):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
05-01 18:38:13.876: ERROR/AndroidRuntime(1455):     at dalvik.system.NativeStart.main(Native Method)
05-01 18:38:13.876: ERROR/AndroidRuntime(1455): Caused by: java.lang.IllegalArgumentException: column 'myQuote' does not exist
05-01 18:38:13.876: ERROR/AndroidRuntime(1455):     at android.database.AbstractCursor.getColumnIndexOrThrow(AbstractCursor.java:314)
05-01 18:38:13.876: ERROR/AndroidRuntime(1455):     at android.widget.SimpleCursorAdapter.findColumns(SimpleCursorAdapter.java:312)
05-01 18:38:13.876: ERROR/AndroidRuntime(1455):     at android.widget.SimpleCursorAdapter.<init>(SimpleCursorAdapter.java:87)
05-01 18:38:13.876: ERROR/AndroidRuntime(1455):     at com.QuoteMachine.Quote.onCreate(Quote.java:42)
05-01 18:38:13.876: ERROR/AndroidRuntime(1455):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1069)
05-01 18:38:13.876: ERROR/AndroidRuntime(1455):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2751)
05-01 18:38:13.876: ERROR/AndroidRuntime(1455):     ... 11 more

Answer 1

In CREATE_QUOTE_TABLE you use "quote text not null, ", and in the logcat you show: Caused by: java.lang.IllegalArgumentException: column 'myQuote' does not exist. What's the value of KEY_QUOTE? It should match the column name in the table.

Test this query:

return qmDB.rawQuery("SELECT _id, myQuote, auth_name, category FROM Quotes WHERE auth_name=?", 
    new String[]{"'Robert Anton Wilson'"});

I believe your problem was not that the query tried to retrieve a column that was not there. The problem I believe is that the cursor you created does not have all the information needed by your adapter (i.e., it's the cursor that does not have the column, not the table).

Answer 2

I'm not 100% sure, but it might be because the documentation states that a Cursor intented to be used with the CursorAdapter needs to contain a reference an "_id" column.