Question

我正在尝试学习SQLite，尝试基本的东西和（正如预期的那样）它并没有真正起作用。我试图创建另一个DB（不同的文件），但错误保持不变。请指导我。我是Android的新手，所以我没有太多的知识。

package net.multiplesystem.nosms.database;
import android.content.ContentValues;
import android.content.Context;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;

public class RegisterAdapter
{
    static final String DATABASE_NAME = "register.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 "+"REGISTER"+
            "( " +"ID"+" integer primary key autoincrement,"+ "NAME text,"+"NUMBER text); ";
    // Variable to hold the database instanceSTER
    public  SQLiteDatabase db;
    // Context of the application using the database.
    private final Context context;
    // Database open/upgrade helper
    private DataBaseHelper dbHelper;
    public  RegisterAdapter(Context _context)
    {
        context = _context;
        dbHelper = new DataBaseHelper(context, DATABASE_NAME, null, DATABASE_VERSION);
    }
    public  RegisterAdapter open() throws SQLException
    {
        db = dbHelper.getWritableDatabase();
        return this;
    }
    public void close()
    {
        db.close();
    }

    public  SQLiteDatabase getDatabaseInstance()
    {
        return db;
    }


    public void insertEntry(String userName,String number)
    {
        ContentValues newValues = new ContentValues();
        // Assign values for each row.
        newValues.put("NUMBER",number);
        newValues.put("NAME", userName);


        // Insert the row into your table
        db.insert("REGISTER", null, newValues);
        ///Toast.makeText(context, "Reminder Is Successfully Saved", Toast.LENGTH_LONG).show();
    }
}

这是我的logcat：

01-13 08:55:49.269: E/SQLiteLog(2588): (1) table REGISTER has no column named NAME
01-13 08:55:49.319: E/SQLiteDatabase(2588): Error inserting NAME=hhhh NUMBER=564
01-13 08:55:49.319: E/SQLiteDatabase(2588): android.database.sqlite.SQLiteException: table REGISTER has no column named NAME (code 1): , while compiling: INSERT INTO REGISTER(NAME,NUMBER) VALUES (?,?)
01-13 08:55:49.319: E/SQLiteDatabase(2588):     at android.database.sqlite.SQLiteConnection.nativePrepareStatement(Native Method)
01-13 08:55:49.319: E/SQLiteDatabase(2588):     at android.database.sqlite.SQLiteConnection.acquirePreparedStatement(SQLiteConnection.java:889)
01-13 08:55:49.319: E/SQLiteDatabase(2588):     at android.database.sqlite.SQLiteConnection.prepare(SQLiteConnection.java:500)
01-13 08:55:49.319: E/SQLiteDatabase(2588):     at android.database.sqlite.SQLiteSession.prepare(SQLiteSession.java:588)
01-13 08:55:49.319: E/SQLiteDatabase(2588):     at android.database.sqlite.SQLiteProgram.<init>(SQLiteProgram.java:58)
01-13 08:55:49.319: E/SQLiteDatabase(2588):     at android.database.sqlite.SQLiteStatement.<init>(SQLiteStatement.java:31)
01-13 08:55:49.319: E/SQLiteDatabase(2588):     at android.database.sqlite.SQLiteDatabase.insertWithOnConflict(SQLiteDatabase.java:1467)
01-13 08:55:49.319: E/SQLiteDatabase(2588):     at android.database.sqlite.SQLiteDatabase.insert(SQLiteDatabase.java:1339)
01-13 08:55:49.319: E/SQLiteDatabase(2588):     at net.multiplesystem.nosms.database.RegisterAdapter.insertEntry(RegisterAdapter.java:65)

package net.multiplesystem.nosms.database;

import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteDatabase.CursorFactory;
import android.database.sqlite.SQLiteOpenHelper;
import android.util.Log;

public class DataBaseHelper extends SQLiteOpenHelper
{
    public DataBaseHelper(Context context, String name,CursorFactory factory, int version)
    {
        super(context, name, factory, version);
    }
    // Called when no database exists in disk and the helper class needs
    // to create a new one.
    @Override
    public void onCreate(SQLiteDatabase _db)
    {
        _db.execSQL(RegisterAdapter.DATABASE_CREATE);

    }
    // Called when there is a database version mismatch meaning that the version
    // of the database on disk needs to be upgraded to the current version.
    @Override
    public void onUpgrade(SQLiteDatabase _db, int _oldVersion, int _newVersion)
    {
        // Log the version upgrade.
        Log.w("TaskDBAdapter", "Upgrading from version " +_oldVersion + " to " +_newVersion + ", which will destroy all old data");

        // Upgrade the existing database to conform to the new version. Multiple
        // previous versions can be handled by comparing _oldVersion and _newVersion
        // values.
        // The simplest case is to drop the old table and create a new one.
        _db.execSQL("DROP TABLE IF EXISTS " + "REGISTER");
        // Create a new one.
        onCreate(_db);
    }
}

Answer 1

你真的创建了这张桌子吗？似乎永远不会执行DATABASE_CREATE脚本。如果您已创建一次然后更改了语句，请确保通过递增数据库版本再次执行该语句。

DATABASE_VERSION = 1，您是否有没有NAME列的先前版本？尝试递增DATABASE_VERSION（可能添加一些日志记录/断点）并查看是否重新创建了数据库。

Answer 2

这可能是因为您在添加属性之前迁移了表文件。我建议你删除你的数据库文件在数据库文件夹中重新创建一个空的数据库文件，然后迁移。并重新运行您的服务器，这应该可以工作。

表*没有名为**的列

2 个答案: