无法在android

Question

我无法创建表格。它显示数据库已创建，我也可以插入一行，但不会创建该表。

public class DatabaseOperations extends SQLiteOpenHelper {

public static final int Database_version = 2;

public static final String Tag = DatabaseOperations.class.getSimpleName();

private static final String SQL_CREATE_ENTRIES =
        "CREATE TABLE " + TableData.TableInfo.TABLE_NAME + " (" +
                TableData.TableInfo.USER_ID + " INTEGER PRIMARY KEY," +
                TableData.TableInfo.USER_PASS +" TEXT "+ "," +
                TableData.TableInfo.USER_EMAIL +" TEXT "+ ");";

public DatabaseOperations(Context context) {
super(context, TableData.TableInfo.DATABASE_NAME, null,Database_version);
    Log.d("Tag", "Database created");
}

@Override
public void onCreate(SQLiteDatabase sdb) {
    sdb.execSQL(SQL_CREATE_ENTRIES);
    Log.d("Tag", "Table created");

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

}

public void putInformation(DatabaseOperations drop, String name, String   pass, String email) {
    SQLiteDatabase SQ = drop.getWritableDatabase();
    ContentValues cv = new ContentValues();
    cv.put(TableData.TableInfo.USER_ID, name);
    cv.put(TableData.TableInfo.USER_PASS, pass);
    cv.put(TableData.TableInfo.USER_EMAIL, email);
    long k = SQ.insert(TableData.TableInfo.TABLE_NAME, null, cv);
    Log.d("Tag", "inert a row");
 }

public Cursor getInformation(DatabaseOperations dop) {
    SQLiteDatabase SQ = dop.getReadableDatabase();
    String[] coloumns = {TableData.TableInfo.USER_ID,  TableData.TableInfo.USER_PASS, TableData.TableInfo.USER_EMAIL};
    Cursor CR = SQ.query(TableData.TableInfo.TABLE_NAME, coloumns, null, null, null, null, null);
    return CR;
}
}

Answer 1

您在CREATE TABLE中的,和USER_EMAIL列之间缺少USER_PASS。

添加后，您可以卸载应用程序以重新创建数据库。 When is SQLiteOpenHelper onCreate() / onUpgrade() run?

Answer 2

您错过了USER PASS类型中的逗号。卸载应用程序并在每次向sqlite数据库添加新内容时再次安装它，因为表结构已更改。因此您需要重新安装新应用程序。

代码应该是这样的

private static final String SQL_CREATE_ENTRIES =         ＆＃34; CREATE TABLE＆＃34; + TableData.TableInfo.TABLE_NAME +＆＃34; （＆＃34; +                 TableData.TableInfo.USER_ID +＆＃34; INTEGER PRIMARY KEY，＆＃34; +                 TableData.TableInfo.USER_PASS +＆＃34; TEXT，＆＃34; +＆＃34;，＆＃34; +                 TableData.TableInfo.USER_EMAIL +＆＃34; TEXT＆＃34; +＆＃34;）＆＃34 ;;