Question

我尝试在数据库中插入一些示例数据。

最初在我的Logcat上出现错误，说“ movie_rating”列不为空。

我注释掉了一段看起来似乎很复杂的代码，没有再次在logcat上看到该消息，但是当我用调试器检查它时仍然得到-1。

这是github仓库：https://github.com/Mf4z/Movie-bookmark/tree/debug-sample-insertion

1-这是样本插入的代码：

public class DatabaseDataWorker {

    private SQLiteDatabase mDb;

    public DatabaseDataWorker(SQLiteDatabase db){

        this.mDb = db;
    }

    public void insertSampleMovies(){

        insertMovies("Big Bang Theory","Series","2","22","Hey Penny","15:12","5");
        insertMovies("Mr Robot","Series","1","2","Ones-and-zer0es","10:11","5");
    }



/*


  private void insertMovies(String name,String type,String timestamp,String rating) {
        ContentValues values = new ContentValues();
        values.put(MovieInfoEntry.COLUMN_MOVIE_NAME,name);
        values.put(MovieInfoEntry.COLUMN_MOVIE_TYPE,type);
        values.put(MovieInfoEntry.COLUMN_MOVIE_TIMESTAMP,timestamp);
        values.put(MovieInfoEntry.COLUMN_MOVIE_NAME,rating);

        String[] nullColumns = {MovieInfoEntry.COLUMN_MOVIE_SEASON,
                MovieInfoEntry.COLUMN_MOVIE_EPISODE,
                MovieInfoEntry.COLUMN_MOVIE_EPISODE_NAME };

        long newRowId = mDb.insertOrThrow(MovieInfoEntry.TABLE_NAME, String.valueOf(nullColumns), values);
    }

*/

    private void insertMovies(String name,String type,String season,String episode,String epName,String timestamp,String rating) {
        ContentValues values = new ContentValues();
        values.put(MovieInfoEntry.COLUMN_MOVIE_NAME,name);
        values.put(MovieInfoEntry.COLUMN_MOVIE_TYPE,type);
        values.put(MovieInfoEntry.COLUMN_MOVIE_SEASON,season);
        values.put(MovieInfoEntry.COLUMN_MOVIE_EPISODE,episode);
        values.put(MovieInfoEntry.COLUMN_MOVIE_EPISODE_NAME,epName);
        values.put(MovieInfoEntry.COLUMN_MOVIE_TIMESTAMP,timestamp);
        values.put(MovieInfoEntry.COLUMN_MOVIE_NAME,rating);

        long newRowId = mDb.insert(MovieInfoEntry.TABLE_NAME, null, values);

    }


}

2-这是数据库架构的代码：

public class MovieBookmarkDatabaseContract {

    private MovieBookmarkDatabaseContract(){}

    public static final class MovieInfoEntry implements BaseColumns {

        public static final String TABLE_NAME = "movie_info";
        public static final String COLUMN_MOVIE_NAME = "movie_name";
        public static final String COLUMN_MOVIE_TYPE = "movie_type";
        public static final String COLUMN_MOVIE_SEASON = "movie_season";
        public static final String COLUMN_MOVIE_EPISODE = "movie_episode";
        public static final String COLUMN_MOVIE_EPISODE_NAME = "movie_episode_name";
        public static final String COLUMN_MOVIE_TIMESTAMP = "movie_timestamp";
        public static final String COLUMN_MOVIE_RATING = "movie_rating";

        //CREATE INDEX movie_info_index ON movie_info(movie_name)
        public static final String INDEX1 = TABLE_NAME+"_index1";
        public static final String SQL_CREATE_INDEX1 =
                "CREATE INDEX " + INDEX1 + " ON " + TABLE_NAME + "(" + COLUMN_MOVIE_NAME + ")";


        /*  CREATE TABLE movie_info (_id INTEGER PRIMARY KEY,movie_name TEXT NOT NULL,movie_type TEXT NOT NULL,
            movie_season TEXT NOT NULL,movie_episode  TEXT NOT NULL,movie_episode_name TEXT,
            movie_timestamp TEXT NOT NULL,movie_rating TEXT NOT NULL)
        */

        public static final String SQL_CREATE_TABLE = "CREATE TABLE "+TABLE_NAME+" ("+
                _ID+" INTEGER PRIMARY KEY, " +
                COLUMN_MOVIE_NAME+" TEXT NOT NULL, "+
                COLUMN_MOVIE_TYPE+" TEXT NOT NULL, "+
                COLUMN_MOVIE_SEASON +" TEXT, "+
                COLUMN_MOVIE_EPISODE +" TEXT, "+
                COLUMN_MOVIE_EPISODE_NAME +" TEXT, "+
                COLUMN_MOVIE_TIMESTAMP + " TEXT NOT NULL, "+
                COLUMN_MOVIE_RATING +" TEXT NOT NULL)";
    }
}

3-数据库帮助程序类：

import com.emef4z.moviebookmark.MovieBookmarkDatabaseContract.MovieInfoEntry;

public class MovieBookmarkOpenHelper extends SQLiteOpenHelper {

    public static final String DATABASE_NAME = "Moviebookmark.db";
    public static final int DATABASE_VERSION = 1;

    public MovieBookmarkOpenHelper(@Nullable Context context) {
        super(context, DATABASE_NAME, null, DATABASE_VERSION);
    }

    @Override
    public void onCreate(SQLiteDatabase db) {
        db.execSQL(MovieInfoEntry.SQL_CREATE_TABLE);
        db.execSQL(MovieInfoEntry.SQL_CREATE_INDEX1);

        DatabaseDataWorker worker = new DatabaseDataWorker(db);
        worker.insertSampleMovies();

    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {

    }
}

4-结合在一起的类：

public class WatchingFragment extends Fragment {

    private MovieBookmarkOpenHelper mOpenHelper;
    private RecyclerView mRecyclerItems;
    private MovieRecyclerAdapter mAdapter;
    private LinearLayoutManager mLinearLayoutManager;


    @Nullable
    @Override
    public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {


        View rootView = inflater.inflate(R.layout.display_list, container, false);

        mOpenHelper = new MovieBookmarkOpenHelper(getContext());

        initializeDisplayContent(rootView);

        return rootView;
    }

    @Override
    public void onDestroyView() {
        mOpenHelper.close();
        super.onDestroyView();
    }


    private void initializeDisplayContent(View rootView){

        mRecyclerItems = (RecyclerView)rootView.findViewById(R.id.recyclerView_list);
        mLinearLayoutManager = new LinearLayoutManager(getContext());
        mAdapter = new MovieRecyclerAdapter(getContext(),null);

        displayMovies();

    }

    private void displayMovies() {
        mRecyclerItems.setLayoutManager(mLinearLayoutManager);
        mRecyclerItems.setAdapter(mAdapter);

        SQLiteDatabase db = mOpenHelper.getReadableDatabase();

    }
}

Answer 1

在 insertMovies 方法（两个签名）中，您为 rating 使用了错误的列名，即

values.put(MovieInfoEntry.COLUMN_MOVIE_NAME,rating);

似乎应该拥有

values.put(MovieInfoEntry.COLUMN_MOVIE_RATING,rating);

因此，评分将被放置在电影名称列中，并且尝试什么（即空）插入到 rating 列中，从而非空冲突

从日志中的消息中可以清楚地看到：-

2019-11-19 10:45:05.586 22025-22025/com.emef4z.moviebookmark E/SQLiteDatabase: Error inserting movie_name=5 movie_type=Series movie_season=1 movie_timestamp=15:12 movie_episode=2 movie_episode_name=1_ones-and-zer0es
    android.database.sqlite.SQLiteConstraintException: NOT NULL constraint failed: movie_info.movie_rating (code 1299 SQLITE_CONSTRAINT_NOTNULL)

消息本身不是致命异常，并且被SQLiteDatabase 插入便捷方法（如设计那样）捕获，因此该方法返回-1，指示未插入行。

P.S。

较短的 insertMovies 方法可能只是：-

private void insertMovies(String name,String type,String timestamp,String rating) {
    insertMovies(name,type,null,null,null,timestamp,rating);
}

尝试在SQLite中插入时出现-1错误

1 个答案: