适用于Android的SQLite DB问题

概述我是 Android的新手,并且一直在关注教程来创建应用程序.我在将数据插入数据库方面遇到了很大困难.我已经尝试了所有我无法想到的东西.数据库类是： package com.mckallip.BeerOnTheWall;import android.content.ContentValues;import android.content.Context;import android.dat 我是 Android的新手,并且一直在关注教程来创建应用程序.我在将数据插入数据库方面遇到了很大困难.我已经尝试了所有我无法想到的东西.数据库类是：

package com.mckallip.BeerOnTheWall;import androID.content.ContentValues;import androID.content.Context;import androID.database.Cursor;import androID.database.sqlException;import androID.database.sqlite.sqliteDatabase;import androID.database.sqlite.sqliteOpenHelper;import androID.util.Log;public class DatabaseUtil{    private static final String TAG = "DatabaseUtil";/** * Database name */private static final String DATABASE_name = "Beer_Database";/** * Database Version */private static final int DATABASE_VERSION = 1;/** * table name */private static final String DATABASE_table = "Beer_List";/** * table columns */public static final String KEY_BEER_name = "beer_name";public static final String KEY_BEER_STYLE = "beer_style";public static final String KEY_BREWERY = "beer_brewery";public static final String KEY_ABV = "beer_abv";public static final String KEY_BEER_score = "beer_score";public static final String KEY_BEER_IMAGE = "beer_image";public static final String KEY_BEER_COMMENTS = "beer_comments";public static final String KEY_ROWID = "_ID";/** * Database creation sql statement */private static final String CREATE_BEER_table =    "CREATE table " + DATABASE_table + " (" + KEY_ROWID + " INTEGER PRIMARY KEY autoINCREMENT," + KEY_BEER_name + " TEXT," + KEY_BEER_STYLE + " TEXT," + KEY_BREWERY + " TEXT," + KEY_ABV + " TEXT," + KEY_BEER_score + "TEXT," + KEY_BEER_IMAGE + " TEXT," + KEY_BEER_COMMENTS + "TEXT );";/** * Context */private final Context mCtx;private DatabaseHelper mDbHelper;private sqliteDatabase mDb;/** * Inner private class. Database Helper class for creating and updating database. */private static class DatabaseHelper extends sqliteOpenHelper {    DatabaseHelper(Context context) {        super(context,DATABASE_name,null,DATABASE_VERSION);    }    /**     * onCreate method is called for the 1st time when database doesn't exists.     */    @OverrIDe    public voID onCreate(sqliteDatabase db) {        Log.i(TAG,"Creating DataBase: " + CREATE_BEER_table);        db.execsql(CREATE_BEER_table);    }    /**     * onUpgrade method is called when database version changes.     */    @OverrIDe    public voID onUpgrade(sqliteDatabase db,int oldVersion,int newVersion) {        Log.w(TAG,"Upgrading database from version " + oldVersion + " to "                + newVersion);    }}protected sqliteDatabase getDataBase(){    return mDb;}/** * Constructor - takes the context to allow the database to be * opened/created * * @param ctx the Context within which to work */public DatabaseUtil(Context ctx) {    this.mCtx = ctx;}/** * This method is used for creating/opening connection * @return instance of DatabaseUtil * @throws sqlException */public DatabaseUtil open() throws sqlException {    mDbHelper = new DatabaseHelper(mCtx);    mDb = mDbHelper.getWritableDatabase();    return this;}/** * This method is used for closing the connection. */public voID close() {    mDbHelper.close();}/** * This method is used to create/insert new record Beer record. * @param sbeer_name * @param sbeer_style * @param sbeer_score * @param sbrewery * @param sabv * @param simageLoc * @param scomments * @return long */public long createBeer(String beer_name,String beer_style,String beer_score,String brewery,String abv,String imageLoc,String comments) {    ContentValues initialValues = new ContentValues();    initialValues.put(KEY_BEER_name,beer_name);    initialValues.put(KEY_BEER_STYLE,beer_style);    initialValues.put(KEY_BREWERY,brewery);    initialValues.put(KEY_ABV,abv);    initialValues.put(KEY_BEER_score,beer_score);    initialValues.put(KEY_BEER_IMAGE,imageLoc);    initialValues.put(KEY_BEER_COMMENTS,comments);    return mDb.insert(DATABASE_table,initialValues);}/** * This method will delete Beer record. * @param rowID * @return boolean */public boolean deleteBeer(long rowID) {    return mDb.delete(DATABASE_table,KEY_ROWID + "=" + rowID,null) > 0;}/** * This method will return Cursor holding all the Beer records. * @return Cursor */public Cursor fetchAllBeers() {    return mDb.query(DATABASE_table,new String[] {KEY_ROWID,KEY_BEER_name,KEY_BEER_STYLE,KEY_BREWERY,KEY_ABV,KEY_BEER_score,KEY_BEER_IMAGE,KEY_BEER_COMMENTS},null);}/** * This method will return Cursor holding the specific Beer record. * @param ID * @return Cursor * @throws sqlException */public Cursor fetchBeer(long ID) throws sqlException {    Cursor mCursor =        mDb.query(true,DATABASE_table,KEY_BEER_COMMENTS                    },KEY_ROWID + "=" + ID,null);    if (mCursor != null) {        mCursor.movetoFirst();    }    return mCursor;}/** * This method will update Beer record. * @param ID * @param name * @param standard * @return boolean */public boolean updateBeer(int ID,String beer_name,String comments) {    ContentValues args = new ContentValues();    args.put(KEY_BEER_name,beer_name);    args.put(KEY_BEER_STYLE,beer_style);    args.put(KEY_BREWERY,brewery);    args.put(KEY_BEER_score,beer_score);    args.put(KEY_ABV,abv);    args.put(KEY_BEER_IMAGE,imageLoc);    args.put(KEY_BEER_COMMENTS,comments);    return mDb.update(DATABASE_table,args,null) > 0;}}

添加数据的类是：

package com.mckallip.BeerOnTheWall;    import androID.content.Context;    import androID.content.Intent;    import androID.database.sqlite.sqliteDatabase;    import androID.os.Bundle;    import androID.vIEw.VIEw;    import androID.vIEw.VIEw.OnClickListener;    import androID.Widget.button;    import androID.Widget.EditText;    import androID.Widget.Spinner;    import androID.Widget.TextVIEw;    import androID.Widget.Toast;    public class AddBeerActivity extends BeerOnTheWallActivity {        private EditText et1;        private EditText et2;        private EditText et3;        private EditText et4;        private Spinner score_spin;        private EditText et5;        @OverrIDe        public voID onCreate(Bundle savedInstanceState) {            super.onCreate(savedInstanceState);            setContentVIEw(R.layout.add_beer);            mDatabase.open();            Context e = getApplicationContext();            String test = "read only";            if (mDatabase.getDataBase().isReadonly()){                test = "Not Readonly" + mDatabase.getDataBase().getPath();            }            Toast t = Toast.makeText(e,test,2);            t.show();            et1 = (EditText) findVIEwByID(R.ID.add_beer_name);            et2 = (EditText)findVIEwByID(R.ID.add_beer_style);            et3 = (EditText) findVIEwByID(R.ID.add_brewery);            et4 = (EditText) findVIEwByID(R.ID.add_abv);            score_spin = (Spinner) findVIEwByID(R.ID.score_spinner);            et5 = (EditText) findVIEwByID(R.ID.add_comments);            ((button)findVIEwByID(R.ID.add_submit)).setonClickListener(new OnClickListener() {                public voID onClick( VIEw v ){                    if (mDatabase.getDataBase().isReadonly())mDatabase.open();                    long beer_ID = mDatabase.createBeer( et1.toString(),et2.toString(),score_spin.toString(),et3.toString(),et4.toString(),"image",et5.toString() );                    Context context = getApplicationContext();                    CharSequence text = "Your beer was added at database position " + beer_ID;                    if ( beer_ID == -1 ){                        text = "There was an error and the beer Could not be added.";                    }                    Toast toast = Toast.makeText(context,text,2);                    toast.show();                    // reset form                    if ( beer_ID != -1 ){                        et1.setText(null);                        et2.setText(null);                        et3.setText(null);                        et4.setText(null);                        et5.setText(null);                    }                }            });         // Handle Go to List button            final button gotoList = (button) findVIEwByID(R.ID.beer_List);            gotoList.setonClickListener(new VIEw.OnClickListener() {                public voID onClick(VIEw v) {                    // Go to other activity that displays beer List                    Intent intent = new Intent(AddBeerActivity.this,BeerListActivity.class);                    startActivity(intent);                }            });        }    }

我添加了toast作为尝试和调试它的方法.第一个声称它是只读的,我无法弄清楚为什么或如何使它可写.

我还将BeerOnTheWallActivity中的DatabaseUtil实例化为静态变量,因此……

public class BeerOnTheWallActivity extends Activity {    protected DatabaseUtil mDatabase = null;     //protected Cursor mCursor = null;    //protected sqliteDatabase mDB = null;    @OverrIDe    protected voID onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        mDatabase = new DatabaseUtil(this.getApplicationContext());        mDatabase.open();    }

当我按下按钮添加数据时,错误日志指出：

07-14 00:31:45.549: ERROR/Database(31512): Error inserting beer_abv=androID.Widget.EditText@47a27ea8 beer_style=androID.Widget.EditText@47a25d28 beer_score=androID.Widget.Spinner@47a2a768 beer_name=androID.Widget.EditText@47a245a8 beer_comments=androID.Widget.EditText@47a2b560 beer_image=image beer_brewery=androID.Widget.EditText@47a26de8

07-14 00:31:45.549: ERROR/Database(31512): androID.database.sqlite.sqliteException: table Beer_List has no column named beer_score:,while compiling: INSERT INTO Beer_List(beer_abv,beer_style,beer_score,beer_name,beer_comments,beer_image,beer_brewery) VALUES(?,?,?);

我想这就是全部.任何帮助将非常感激.

解决方法 请检查下面

你的代码是

private static final String CREATE_BEER_table =    "CREATE table " + DATABASE_table + " (" + KEY_ROWID + " INTEGER PRIMARY KEY autoINCREMENT," + KEY_BEER_COMMENTS + "TEXT );";

改成使用了这个

private static final String CREATE_BEER_table =    "CREATE table " + DATABASE_table + " (" + KEY_ROWID + " INTEGER PRIMARY KEY autoINCREMENT," + KEY_BEER_score + " TEXT," + KEY_BEER_COMMENTS + " TEXT );";

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